Novel compounds with analgesic effect

ABSTRACT

Compounds of the formula (I)  
                 
 
     as well as their pharmaceutically acceptable salts, and pharmaceutical compositions comprising the novel compounds. The novel compounds of the formula (I) are useful in the management of pain.

FIELD OF THE INVENTION

[0001] The present invention is related to novel compounds, to a process for their preparation, their use and pharmaceutical compositions comprising the novel compounds. The novel compounds are used in therapy, and in particular for the treatment of pain.

BACKGROUND AND PRIOR ART

[0002] The δ receptor has been identified as having a role, in many bodily functions such as circulatory and pain systems. Ligands for the δ receptor may therefore find potential use as analgesics, and/or as antihypertensive agents. Ligands for the δ receptor have also been shown to posess immunomodulatory activities.

[0003] The identification of at least three different populations of opioid receptors (μ, δ and κ) is now well established and all three are apparent in both central and peripheral nervous systems of many species including man. Analgesia has been observed in various animal models when one or more of these receptors has been activated.

[0004] With few exceptions, currently available selective opioid δ ligands are peptidic in nature and are unsuitable for administration by systemic routes. Some non-peptidic δ antagonists have been available for some time (see Takemori and Portoghese, 1992, Ann. Rev. Pharmacol. Tox., 32: 239-269. for review). These compounds, e.g. naltrindole, suffer from rather poor (i.e., <10-fold) selectivity for the δ receptor vs μ receptor binding and exhibit no analgesic activity, a fact which underscores the need for the development of highly selective non-peptidic δ agonists.

[0005] Recently, a non-peptidic δ agonist, BW 373U86, was described by Chang et al., 1993, J. Pharmacol. Exp. Ther., 267: 852-857., as the first δ-selective non-peptide with analgesic activity, however, it shows significant affinity for the μ receptor.

[0006] Thus, the problem underlying the present invention was to find new analgesics having excellent analgesic effects, but also with an improved side-effect profile over current μ agonists and potential oral efficacy.

[0007] Analgesics that have been identified and are existing in the prior art have many disadvantages in that they suffer from poor pharmacokinetics and are not analgesic when administered by systemic routes. Also, it has been documented that preferred compounds, described within the prior art, show significant convulsive effects when administered systemically.

[0008] In WO 93/15062 and WO 95/045051, some diarylmethylpiperazine and diarylmethylpiperidine compounds, including BW 373U86, are disclosed, but these prior art compounds are structurally distinct from the compounds acccording to the present invention.

[0009] The problem mentioned above has been solved by developing novel piperazine and piperidine compounds, as will be described below.

[0010] Outline of the Invention

[0011] The novel compounds according to the present invention are defined by the formula (I)

[0012] wherein

[0013] G is a carbon atom or a nitrogen atom;

[0014] A is selected from

[0015] (i) phenyl substituted by any of —COOH, —CONH₂, COOCH₃, —CN, NH₂ or —COCH₃;

[0016] (ii) naphtyl, benzofuranyl, and quinolinyl; and

[0017]  wherein the phenyl ring of each A substituent may be optionally and independently substituted by 1 or 2 substituents selected from hydrogen, CH₃, (CH₂)_(o)CF₃, halogen, CONR⁷R⁸, CO₂R⁷, COR⁷, (CH₂)_(o)NR⁷R⁸, (CH₂)_(o)CH₃(CH₂)_(o)SOR⁷, (CH₂)_(o)SO₂R⁷ and (CH₂)_(o)SO₂NR⁷R⁸ wherein o is 0, 1, or 2, and R⁷ and R⁸ are defined below;

[0018] R¹ is selected from hydrogen; a branched or straight C₁-C₆ alkyl, C₁-C₆ alkenyl, —CO(C₁-C₆ alkyl); (C₁-C₆ alkyl)-B wherein B is as defined below, C₃-C₈ cycloalkyl, C₄-C₈ (alkyl-cycloalkyl) wherein alkyl is C₁-C₂ alkyl and cycloalkyl is C₃-C₆ cycloalkyl; C₆-C₁₀ aryl; and heteroaryl having from 5-10 atoms selected from any of C, S, N and O; and whereby the C₆-C₁₀ aryl and the heteroaryl may optionally be substituted by 1 or 2 substituents selected from hydrogen, CH₃, (CH₂)_(o)CF₃, halogen, CONR⁷R⁸, CO₂R⁷, COR⁷, (CH₂)_(o)NR⁷R⁸, (CH₂)_(o)CH₃(CH₂)_(o)SOR⁷, (CH₂)_(o)SO₂R⁷ and (CH₂)_(o)SO₂NR⁷R⁸, wherein o is 0, 1, or 2, and R⁷ and R⁸ are as defined below;

[0019] R⁷ and R⁸ is each and independently as defined for R¹ above;

[0020] R² is selected from hydrogen, CH₃, OR¹, CO₂R¹, and CH₂CO₂R¹ wherein

[0021] R¹ is as defined above;

[0022] R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, and R¹⁸, is each and independently as defined for R¹ above;

[0023] B is a substituted or unsubstituted aromatic; an optionally substituted C₅-C₁₀ hydroaromatic; a heteroaromatic or a heterohydroaromatic moiety, each having from 5 to 10 atoms selected from any of C, S, N and O, and each being optionally and independently substituted by 1 or 2 substituents independently selected from hydrogen, CH₃, CF₃, halogen, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)COR⁷R⁸, (CH₂)_(p)CO₂R⁷, OR⁷, (CH₂)_(p)SOR⁷, (CH₂)_(p)SO₂R⁷, and (CH₂)_(p)SO₂NR⁷R⁸;

[0024] wherein p is 0, 1, 2 or 3 and wherein R⁷ and R⁸ are as defined above;

[0025] R³, R⁴, R⁵ and R⁶ is each and independently selected from

[0026] R⁷, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)CO₂R⁷, (CH₂)_(p)Ph, (CH₂)_(p)(p-OH Ph), (CH₂)_(p)-3-indolyl, (CH₂)_(p)SR⁷, and (CH₂)_(p)OR⁷;

[0027] wherein p is 0, 1, 2, 3, or 4, and R⁷ and R⁸ are as defined above;

[0028] with the proviso that when A is a phenyl ring substituted by a —CN group or by a —NH₂ group, B may not be

[0029]  wherein

[0030] Z¹ is hydroxy, and esters thereof;

[0031] hydroxymethyl, and esters thereof; or

[0032] amino, and carboxamides and sulfonamides.

[0033] Within the scope of the invention are also pharmaceutically acceptable salts of the compounds of the formula (I), as well as isomers, hydrates, isoforms and prodrugs thereof.

[0034] Preferred compounds according to the invention are compounds of the formula (I) wherein

[0035] G is a carbon atom or a nitrogen atom;

[0036] A is selected from

[0037] (i) phenyl substituted by any of —COOH, —CONH₂, COOCH₃, —CN, NH₂ or —COCH₃;

[0038] (ii) naphtyl, benzofuranyl, and quinolinyl; and

[0039]  wherein the phenyl ring of each A substituent may be optionally and independently substituted by 1 or 2 substituents selected from hydrogen, CH₃, (CH₂)_(o)CF₃, halogen, CONR⁷R⁸, COR⁷, COR⁷, (CH₂)_(o)NR⁷R⁸, (CH₂)CH₃(CH₂)_(o)OR⁷, (CH₂)_(o)OR⁷ and (CH₂ NR⁷R⁸, wherein 0 is 0, 1, or 2, and R⁷ and R⁸ are as defined below;

[0040] R¹, R⁷ and R⁸ is each and independently selected from hydrogen; a branched or straight C₁-C₄ alkyl, allyl, —CO(C₁-C₆ alkyl); (C₁-C₆ alkyl)-B wherein B is as defined below; C₃-C₅ cycloalkyl, C₄-C₈ (alkyl-cycloalkyl) wherein alkyl is C₁-C₂ alkyl and cycloalkyl is C₃-C₆ cycloalkyl; and phenyl;

[0041] R² is hydrogen, methyl, or OR¹ wherein R¹ is as defined above;

[0042] R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, and R¹⁸ is each and independently as defined for R¹ above;

[0043] B is selected from phenyl, naphthyl, indolyl, benzofuranyl, dihydrobenzofuranyl benzothiophenyl, pyrryl, furanyl, quinolinyl, isoquinolinyl, cyclohexyl, cyclohexenyl, cyclopentyl, cyclopentenyl, indanyl, indenyl, tetrahydronaphthyl, tetrahydroquinyl, tetrahydroisoquinolinyl, tetrahydrofuranyl, pyrrolidinyl, indazolinyl, and

[0044]  each B group being optionally substituted by 1-2 substituents independently selected from hydrogen, CH₃, CF₃, halogen, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)COR⁷, (CH₂)_(p)CO₂R⁷, and OR⁷;

[0045] wherein p is 0 or 1, and wherein R⁷ and R⁸ are as defined above; and

[0046] R³, R⁴, R⁵ and R⁶ is each and independently selected from hydrogen, CH₃, CH(Me)₂, CH₂CH(Me)₂, CH(Me)CH₂CH₃(CH₂)CONR⁷, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)CO₂R⁷, (CH₂)_(p)Ph, (CH₂)_(p)(p-OH Ph), (CH₂)-3-indolyl, (CH₂)_(p)SR⁷, and (CH₂)_(p)OR⁷, wherein p is 0, 1, 2, or 3, and wherein R⁷ and R⁸ are as defined above;

[0047] with the proviso that when A is a phenyl ring substituted by a —CN group or by a —NH₂ group, B may not be.

[0048]  wherein

[0049] Z¹ is hydroxy, and esters thereof;

[0050] hydroxymethyl, and esters thereof; or

[0051] amino, and carboxamides and sulfonamides.

[0052] Especially preferred compounds according to the invention are compounds of the formula (I) wherein

[0053] G is a nitrogen atom;

[0054] A is selected from

[0055]  wherein

[0056] R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, and R¹⁸ is each an ethyl group;

[0057] R¹ is selected from hydrogen, methyl, ethyl, allyl, or CH₂-cyclopropyl;

[0058] R² is H, methyl, or OR¹, wherein R1 is as defined above;

[0059] B is selected from phenyl, naphthyl, indolyl, benzofuranyl, dihydrobenzofuranyl, benzothiophenyl, furanyl, quinolinyl, isoquinolinyl, cyclohexyl, cyclohexenyl, cyclopentyl, cyclopentenyl, indanyl, indenyl, tetrahydronaphthyl, tetrahydroquinyl, tetrahydroisoquinolinyl, tetrahydrofuranyl, indazolinyl, and

[0060]  each B group being optionally substituted by 1-2 substituents independently selected from hydrogen, methyl, CF₃, halogen, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)COR⁷, (CH₂)_(p)CO₂R⁷, and OR⁷,

[0061] wherein p is 0, 1, or 2, and wherein R⁷ and R⁸ are as defined for R¹ above;

[0062] R³, R⁴, R⁵ and R⁶ is each and independently selected from H, CH₃, CH(Me)₂, is CH₂CH(Me)₂, CH(Me)CH₂CH₃(CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)CO₂R⁷, (CH₂)_(p)Ph, (CH₂)_(p)(p-OH Ph), (CH₂)_(p)-3-indolyl, (CH₂)_(p)SR⁷, and (CH₂)_(p)OR⁷

[0063] wherein p is 0, 1 or 2, and wherein R⁷ and R⁸ are as defined above;

[0064] The substituents A and B respectively, may optionally be substituted at any position of the ring.

[0065] By “halogen” we mean chloro, fluoro, bromo and iodo.

[0066] By “aryl” we mean an aromatic ring having from 6-10 carbon atoms, such as phenyl and naphtyl.

[0067] By “heteroaryl” we mean an aromatic ring in which one or more of the 5-10 atoms in the ring are elements other than carbon, such as N, S and O.

[0068] By “hydroaromatic” we mean a partly or fully saturated aromatic ring structure having 5-10 carbon atoms in the ring.

[0069] By “heterohydroaromatic” we mean a partly or fully saturated aromatic ring structure in which one or more of the 5-10 atoms in the ring are-elements other than carbon, such as N, S and O.

[0070] By “isomers” we mean compounds of the formula (I), which differ by the position of their functional group and/or orientation. By “orientation” we mean stereoisomers, diastereoisomers, regioisomers and enantiomers.

[0071] By “isoforms” we mean compounds of the formula (I) which differ by their crystal lattice, such as crystalline compound and amorphous compounds.

[0072] By “prodrug” we mean pharmacologically acceptable derivatives, e.g. esters and amides, such the resulting biotransformation product of the derivative is the active drug. The reference by Goodman and Gilmans, The Pharmacological basis of Therapeutics, 8th ed., McGraw-Hill, Int. Ed. 1992, “Biotransformation of Drugs, p. 13-15, describing prodrugs generally, is hereby incorporated.

[0073] The novel compounds of the present invention are useful in therapy, especially for the treatment of pain.

[0074] The compounds are also useful for modulating the analgesic effects acting at the μ opioid receptor subtype, the modulation of side effects seen with agents acting at the μ opioid receptor subtype such as morphine, especially respiratory depression, gut motility and abuse liability.

[0075] Compounds of the invention are also useful as immunomodulators, especially for autoimmune diseases, such as arthritis, for skin grafts, organ transplants and similar surgical needs, for collagen diseases, various allergies, for use as anti tumour agents and anti viral agents.

[0076] Compounds of the invention are useful in disease states where degeneration or dysfunction of opioid receptors is present or implicated in that paradigm. This may involve the use of isotopically labeled versions of the compounds of the invention in diagnostic techniques and imaging applications such as positron emission tomography (PET).

[0077] Compounds of the invention are useful for the treatment of diarrhea, depression, urinary incontinence, various mental illnesses, cough, lung oedema, various gastrointestinal disorders, spinal injury and drug addiction, including the treatment of alcohol, nicotine, opioid and other drug abuse and for disorders of the sympathetic nervous system for example hypertension.

[0078] The best mode of performing the present invention known at present, is to use the compounds according to Example 21 (compound 33), Example 22 (compound 34), Example 23 (compound 37), Example 24 (compound 38), Example 25 (compound 41), Example 26 (compound 42), Example 27 (compound 45), Example 29 (compound 51), Example 30 (compound 54), Example 35 (compound 64), Example 36 (compound 65), Example 50, and Example 51. The numbering of the compounds is in accordance with the Examples below, as well as in accordance with the numbering in the Schemes presented in the following.

[0079] Methods of Preparation

[0080] Generalized Method A

[0081] An aldehyde or ketone is treated with a nucleophile such as a Grignard or organolithium species to produce the corresponding alcohol. This alcohol may then be converted into a suitable leaving group (X), such as an ester, sulphonate or halide which may in turn be displaced with a nucleophilic species such as a substituted or unsubstituted piperazine. N-(4)-unsubstituted piperazine derivatives may then be suitably substituted with a variety of groups via their organo halide or equivalent species, or acylated with a number of different acylating compounds. This sequence of events will give rise to compounds according to general formula I.

[0082] Generalized Method B

[0083] An N-protected amino acid, as its activated ester, may be reacted with a second amino acid ester. On treatment with an acid this species may then cyclize to form a piperazinedione. This dione may be reduced via a number of standard methods to the corresponding piperazine (e.g. a reducing agent such as lithium aluminium hydride, by conversion to the thioamide and subsequent desulphurization, hydrogenation in the presence of POCl₃ etc.) This piperazine may then be alkylated or acylated on one or more of the nitrogens and/or may be used subsequently in generalized method A.

[0084] Deprotection of functional groups or further modifications may then be necessary, these are described for each individual case. Specific examples for the above transformations are given in the experimental.

[0085] All transformations contemplated use reagents (including salts) and solvents known to the art of chemistry and to biotransformations carried out in a suitable biological medium to bring about these transformations and includes all reaction enhancing agents (e.g. HMPA), and chiral resolutions using chiral salt formation and chiral biological resolutions.

DETAILED DESCRIPTION OF THE INVENTION

[0086] The invention will now be described in more detail by the following examples, which are not to be construed as limiting the invention.

EXAMPLES

[0087] The compounds according to Examples 1-3 were synthesized as shown in Scheme 1 above.

[0088] A.

[0089] I. Preparation of 3-methoxy-α-(1-naphthyl)benzyl Alcohol (Compound 1)

[0090] To a solution of 3-bromoanisole (5.61 g, 30.0 mmol) in dry THF (80 mL) was dropwise added n-butyl lithium-hexane solution (1.6 M, 37.5 ml., 60 mmol) under nitrogen at −78° C. The reaction mixture was allowed to warm to r.t. in 2 h and cooled down again to −78° C. prior to addition of 1-naphthaldehyde (4.69 g, 30.0 mmol, in 10 mL THF). The mixture was warmed to r.t. in 3 h, and then quenched with aqueous NH₄Cl solution, extracted with ethyl acetate (3×50 mL). The combined organic phases were washed with brine, dried over MgSO₄. Removal of solvents in vacuo provided 3-methoxy-α-(1-naphthyl)benzyl alcohol (4.25 g, 54%). GC-MS (R_(t)=10.41 min) 264 (M⁺), 245, 231, 215, 202, 155, 135, 128, 109.

[0091] II. Preparation of 3-methoxy-α-(1-naphthyl)benzyl Chloride (Compound 2)

[0092] To a solution of 3-methoxy-α-(1-naphthyl)benzyl alcohol (2.5 g, 9.5 mmol) in diethyl ether (5 mL) was added 35% hydrochloric acid (10 mL) at 0° C. The reaction mixture was warmed to r.t. in 1 h, and then extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with aqueous NH₄Cl solution and brine, dried over MgSO₄. Evaporation of solvents gave 3-methoxy-α-(1-naphthyl)benzyl chloride (1.94 g, 72%). GC-MS (R_(t)=10.30 min) 282 (M⁺), 247, 232, 215, 202, 189, 163, 151, 139, 123, 101.

Example 1

[0093] Preparation of (±)-trans-1-(3-methoxy-α-(1-naphthyl)benzyl)-2,5-dimethylpiperazine (Compound 3)

[0094] A mixture of trans-2,5-dimethylpiperazine (456 mg, 4.0 mmol), 3-methoxy-α-(1-naphthyl)benzyl chloride (430 mg, 1.5 mmol) and triethylamine (2 mL) in dry DMF (10 mL) was refluxed for 2 h under nitrogen. after cooling down to r.t., the reaction mixture was quenched with 1 N aqueous NH₄OH solution, and extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with 0.5 N aqueous NaOH solution, saturated aqueous NH₄C and brine, dried over MgSO₄. Removal of solvents gave (±)-trans-1-(3-methoxy-α-(1′-naphthyl)benzyl)-2,5-dimethylpiperazine, which was used directly in the next step: GC-MS (two isomers: R_(t)=12.98 & 13.10 min) 360 (M⁺), 301, 276, 247, 232, 215, 189, 165, 131, 113.

Example 2 and 3

[0095] Preparation of (±)-3-((αR*/S*)-α-((2S*,5R)-4-Allyl-2,5-dimethyl-piperazinyl)-1-naphthyl)anisole (Compounds 4 & 5)

[0096] A mixture of above (±)-trans-1-(3-methoxy-α-(1-naphthyl)benzyl)-2,5-dimethylpiperazine, K₂CO₃ (276 mg, 2.0 mmol) and allyl bromide (242 mg, 2.0 mmol) in DMF (5 mL)/THF (10 mL) was stirred for 3 h at r.t. The reaction mixture was quenched with 1 N NH₄OH and extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with saturated aqueous NH₄Cl and brine, dried over MgSO₄. Evaporation of solvents provided crude (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2-methyl-piperazinyl)-1-naphthyl)anisole, which were purified by silica gel column eluting with AcOEt-Hexane (2:98→100:0) to yield the two isomers (totally 267 mg, 45% from 2):

[0097] The first isomer, compound 4: GC-MS (R_(t)=14.84 min) 401.15 (M⁺+1, 0.3%), 400.15 (M⁺, 0.9), 359.15 (0.6), 330.15 (0.4), 302.15 (3.2), 274.15 (8.0), 247.05 (23.0), 215.10 (12.7), 202.05 (7.8), 153.15 (100), 126.15 (10.1); δ_(H) (400 MHz, CDCl₃) 1.02 (d, J=6.4 Hz, 6H), 2.15 (dd, J=11.2, 6.4 Hz, 1H), 2.31 (dd, J=11.2, 6.4 Hz, 1H), 2.60 (m, 1H), 2.74 (dd, J=11.2, 3.2 Hz, 1H), 2.80 (dd, J=11.2, 3.2 Hz, 1H), 2.94 (dd, J=13.6, 7.2 Hz, 1H), 3.03 (dt, J=6.4, 3.2 Hz, 1H), 3.20 (dd, J=13.6, 5.6 Hz, 1H), 3.73 (s, 3H), 5.12. (m, 2H), 5.73 (brs, 1H), 5.83 (m, 1H), 6.68 (dd, J=8.0, 2.4 Hz, 1H), 7.00 (d, J=8.0 Hz, 1H), 7.12 (m, 2H), 7.42 (m, 3H), 7.62 (d, J=7.2 Hz, 1H), 7.71 (d, J=8.0 Hz, 1H), 7.80 (d, J=8.0 Hz, 1H), 8.28 (brs, 1H); δ_(C-13) (100 MHz, CDCl₃) 13.2, 14.2, 35.6, 52.1, 53.0, 55.1, 55.2, 57.2, 63.8, 111.6, 114.4, 117.2, 121.1, 123.8, 125.2, 125.7, 125.8, 127.2, 127.5, 127.8, 128.9, 132.1, 134.0, 135.5, 137.4, 145.5, 159.5.

[0098] Its HCl salt: m.p. 124-135° C. (Ether); v_(max) (KBr) cm⁻¹ 3483, 1601, 1264; Anal.Calcd.for C₂₇H₃₂N₂O.2HCl.1.0H₂O: C, 65.98; H, 7.38; N, 5.70. Found: C, 66.12; H, 7.25; N, 5.42.

[0099] The second isomer, compound 5: GC-MS (R_(t)=14.65 min) 401.25 (M⁺+1, 0.2%), 400.25 (M⁺, 0.8), 359.15 (0.4), 330.15 (0.4), 302.15 (3.1), 274.15 (8.0), 247.05 (21.7), 215.10 (13.0), 202.05 (7.0), 153.15 (100), 126.15 (9.7); δ_(H) (400 MHz, CDCl₃) 0.93 (d, J=6.4 Hz, 3H), 1.15 (d, J=6.4 Hz, 3H), 2.14 (m, 2H), 2.37 (m, 1H), 2.60 (dd, J=11.6, 2.8 Hz, 1H), 2.84 (m, 2H), 2.96 (m, 1H), 3.35 (dd, J=13.2, 5.2 Hz, 1H), 5.13 (m, 2H), 5.81 (s, 1H), 5.86 (m, 1H), 6.73 (dd, J=8.0, 2.8 Hz, H), 6.81 (s, 1H), 6.84 (d, J=8.0 Hz, 1H), 7.16 (m, 1H), 7.40 (m, 3H), 7.70 (m, 2H), 7.80 (d, J=8.0 Hz, 1H), 8.15 (d, J=8.0 Hz, 1H); δ_(C-13) (100 MHz, CDCl₃ 15.7, 16.3, 38.8, 53.6, 55.0, 55.6, 56.8, 59.3, 63.6, 111.5, 115.6, 117.4, 121.9, 124.6, 125.0, 125.1, 125.4, 126.2, 127.4, 128.5, 128.9, 131.6, 133.9, 135.0, 138.3, 142.2, 159.4.

[0100] Its HCl salt m.p. 150.5-153° C. (Ether); v_(max) (KBr) cm⁻¹ 3483, 1600, 1262; Anal.Calcd.for C₂₇H₃₂N₂O.2HCl.0.75H₂O: C, 66.59; H, 7.35; N, 5.75. Found: C, 66.41; H, 7.03; N, 5.48.

[0101] The compounds according to Examples 46 were synthesized as shown in Scheme 2 above.

[0102] B.

[0103] I. Preparation of 3-methoxy-α-(2-naphthyl)benzyl Alcohol (Compound 6)

[0104] The compound 6 was prepared by following the synthesis procedure as described for compound 1, but substituting 1-naphtaldehyde for 2-naphtaldehyde.

[0105] GC-MS (R_(t)=10.68 min) 264 (M⁺), 247, 231, 215, 202, 155, 135, 128, 109; δ_(H) (400 MHz, CDCl₃) 3.15 (brs, 1H), 3.59 (s, 3H), 5.71 (s, 1H), 6.69 (dd, J=8.4, 2.8 Hz, 1H), 6.87 (m, 2H), 7.11 (t, J=8.0 Hz, 1H), 7.29 (dd, J=8.4, 1.2 Hz, 1H), 7.35 (m, 2H), 7.63 (d, J=8.4 Hz, 1H), 7.70 (m, 3H); δ_(C-13) (100 MHz, CDCl₃) 55.0, 75.9, 112.1, 112.8, 118.9, 124.6, 124.9, 125.7, 125.9, 127.5, 127.9, 128.1, 12943, 132.7, 133.1, 141.0, 145.2, 159.5.

[0106] II. Preparation of 3-methoxy-α-(2-naphthyl)benzyl Chloride (Compound 7)

[0107] The compound 7 was prepared by following the synthesis procedure as described for compound 2, but substituting compound 1 for compound 6.

[0108] GC-MS (R_(t)=10.58 min) 282 (M⁺), 247, 231, 215, 202, 189, 151, 123, 101.

Example 4

[0109] Preparation of (±)-trans-1-(3-methoxy-α-(2-naphthyl)benzyl)-2,5-dimethylpiperazine (Compound 8)

[0110] The compound 8 was prepared by following the synthesis procedure as described for compound 3, but substituting compound 2 for compound 7.

[0111] Used directly in the next step: GC-MS (R_(t)=14.03 min) 360 (M⁺), 331, 301, 276, 247, 219, 169, 131, 113.

Example 5 and 6

[0112] Preparation of (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-2-naphthyl)anisole (Compounds 9 & 10)

[0113] The compounds of these Examples were prepared by following the synthesis procedure as described for Examples 2 and 3, but substituting compound 3 for compound 8.

[0114] Compound 9 (one pure isomer): GC-MS (R_(t)=16.05 min) 401.25 (0.2%), 400.25 (0.8), 359.15 (0.4), 330.15 (0.4), 302.15 (3.1), 274.15 (8.0), 247.05 (21.7), 215.10 (13.0), 202.05 (7.0), 153.15 (100), 126.15 (9.7); δ_(H) (400 MHz, CDCl₃) 1.36 (d, J=6.4 Hz, 3H), 1.41 (d, J=6.4 Hz, 3H), 3.16 (dd, J=13.2, 2.4 Hz, 1H), 3.26 (d, J=13.2 Hz, 1H), 3.46 (m, 1H), 3.86 (s, 3H), 3.94 (dd, J=11.2, 2.8 Hz, 1H), 4.10 (m, 2H), 4.46 (m, 2H), 5.58 (m, 2H), 5.78 (s, 1H), 6.05 (m, 1H), 6.96 (dd, J=8.0, 2.0 Hz, 1H), 7.18 (s, 1H), 7.33 (m, 1H), 7.44 (m, 1H), 7.50 (m, 2H), 7.83 (m, 3H), 8.04 (d, J=8.0 Hz, 1H), 8.13 (s, 1H), 13.6 (brs, 2H).

[0115] Its HCl salt m.p. 129-138° C. (Ether); v_(max) (KBr) cm⁻¹ 3426, 1600, 1262; Anal.Calcd.for C₂₇H₃₂N₂O.2HCl.0.75H₂O: C, 66.59; H, 7.35; N, 5.75. Found: C, 66.80; H, 7.11; N, 5.42.

[0116] Compound 10 (a mixture of two isomers) Its HCl salt: m.p. 160-162.5° C. (Ether); v_(max) (KBr) cm⁻¹ 3380, 1600, 1261; Anal.Calcd.for C₂₇H₃₂N₂O.2HCl.0.50H₂O: C, 67.21; H, 7.31; N, 5.81. Found: C, 67.13; H, 6.97; N, 5.47.

[0117] The compounds according to Examples 7-11 were synthesized as shown in Scheme 3 above.

[0118] C.

[0119] I. Preparation of 3-methoxy-α-(2-benzofuranyl)benzyl Alcohol (Compound 11)

[0120] The compound of this Example was prepared by following the synthesis procedure as described for Example 1.

[0121] GC-MS (R_(t)=9.54 min) 254.15 (M⁺, 100%), 237.10 (73.8), 221.05 (19.6), 194.10 (17.8), 165.10 (30.3), 147.05 (76.7), 135.10 (69.2), 118.10 (35.4), 108.10 (26.5), 91.10 (47.1); δ_(H) (400 MHz, CDCl₃) 3.21 (brs, 1H), 3.72 (s, 3H), 5.82 (s, 1H), 6.47 (s, 1H), 6.80-7.50 (m, 8H).

[0122] II. Preparation of 3-methoxy-α-(2-benzofuranyl)benzyl Chloride (Compound 12)

[0123] The compound 12 was prepared by following the synthesis procedure as described for compound 2, but substituting compound 1 for compound 11.

[0124] GC-MS (R_(t)=9.08 min) 272.05 (M⁺, 4.1%), 237.10 (100), 221.05 (4.5), 194.10 (14.7), 165.10 (23.1); δ_(H) (400 MHz, CDCl₃) 3.78 (s, 3H), 6.11 (s, 1H), 6.56 (s, 1H), 6.85-7.50 (m, 8H).

Example 7

[0125] Preparation of (±)-trans-1-(3-methoxy-α-(2′-benzofuranyl)benzyl)-2,5-dimethylpiperazine (Compound 13)

[0126] The compound 13 was prepared by following the synthesis procedure as described for compound 3, but substituting compound 2 for compound 12.

[0127] GC-MS (R_(t)=11.87 min & R_(t)=12.09 inn) 351.15 (M⁺+1, 2.2%), 350.15 (M⁺, 8.6), 321.20 (0.4), 308.15 (0.2), 294.20 (18.3), 266.10 (58.6), 231.10 (100), 221.05 (3.0), 194.10 (10.0), 178.05 (4.1), 165.10 (13.0), 131.05 (2.9), 113.10 (43.8); δ_(H) (400 MHz, CDCl₃) (isomer at R_(t)=11.87 min) 0.92 (d, J=6.4 Hz, 3H), 1.20 (d, J=6.4 Hz, 3H), 1.92 (dd, J=11.2, 10.8 Hz, 1H), 2.44 (m, 1H), 2.69 (dd, J=11.2, 10.8 Hz, 1H), 2.83 (m, 2H), 2.90 (m, 1H), 3.78 (s, 3H), 5.56 (s, 1H), 6.61 (s, 1H), 6.80 (d, J=8.0 Hz, 1H), 7.00 (d, J=8.0 Hz, 1H), 7.10 (s, 1H), 7.24 (m, 3H), 7.46 (d, J=8.0 Hz, 1H), 7.56 (d, J=8.0 Hz, 1H); (isomer at R_(t)=12.09 min) 0.96 (d, J=6.4 Hz, 3H), 1.22 (d, J=6.4 Hz, 3H), 1.83 (dd, J=11.2, 10.8 Hz, 1H), 2.40 (m, 1H), 2.65 (m, 1H), 2.90 (m, 3H), 3.80 (s, 3H), 5.47 (s, 1H), 6.63 (s, 1H), 6.84 (m, 2H), 7.21 (m, 2H), 7.24 (m, 2H). 7.46 (d, J=8.0 Hz, 1H), 7.51 (d, J=8.0 Hz, 1H).

[0128] Its HCl salt: m.p. 115-125° C. (Ether); v_(max) (KBr) cm⁻¹ 3373, 1595, 1257; Anal.Calcd.for C₂₂H₂₆N₂.1.70HCl.0.20H₂O: C, 63.51; H, 6.81; N, 6.73. Found: C, 63.60; H, 6.80; N, 6.70.

Example 8 and 9

[0129] Preparation of (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-2-benzofuranyl)anisole (Compounds 14 & 15)

[0130] The compounds of these Examples were prepared by following the synthesis procedure as described for Examples 2 and 3, but substituting compound 3 for compound 13.

[0131] The first isomer, compound 14: GC-MS (R_(t)=13.03 min) 390.20 (M⁺, 1.5%), 349.15 (0.4), 320.10 (0.3), 292.10 (1.7), 264.10 (4.2), 237.10 (25.1), 221.05 (1.4), 194.10 (5.2), 165.10 (5.5), 153.15 (100), 126.15 (4.8), 98.05 (8.7), 84.10 (17.8); δ_(H) (400 MHz, CDCl₃) 0.97 (d, J=6.4 Hz, 3H), 1.21 (d, J=6.4 Hz, 3H), 2.12 (m, 2H), 2.35 (m, 1H), 2.65 (m, 1H), 2.75 (dd, J=11.6, 2.4 Hz, 1H), 2.81 (m, 3H), 3.42 (dd, J=13.6, 5.2 Hz, 1H), 3.78 (s, 3H), 5.14 (m, 2H), 5.51 (s, 1H), 5.85 (m, 1H), 6.61 (s, 1H), 6.81 (dd, J=8.0, 2.4 Hz, 1H), 7.01 (d, J=8.0 Hz, 1H), 7.11 (s, 1H), 7.24 (m, 3H), 7.44 (d, J=8.0 Hz, 1H), 7.54 (d, J=8.0 Hz, 1H); δ_(C-13) (100 MHz, CDCl₃) 17.2, 17.5, 53.1, 54.4, 55.2, 56.0, 56.6, 59.2, 60.4, 106.8, 111.3, 112.1, 114.2, 117.8, 120.6, 120.7, 122.6, 123.8, 128.1, 129.0, 134.8, 141.4, 154.9, 155.2, 159.6.

[0132] Its HCl salt: m.p. 122-128° C. (Ether); v_(max) (KBr) cm⁻¹ 13490, 1602, 1253; Anal.Calcd.for C₂₅H₃₀N₂O₂.2HCl.0.25H₂O: C, 64.17; H, 7.00; N, 5.99. Found: C, 64.27; H, 6.92; N, 5.92.

[0133] The second isomer, compound 15: GC-MS (R_(t)=13.23 min) 390.20 (M⁺, 3.1%), 349.15 (0.5), 292.10 (2.2), 264.10 (5.5), 237.10 (33.2), 221.05 (1.8), 194.10 (7.1), 165.10 (7.7), 153.15 (100), 126.15 (7.1), 98.15 (18.4), 84.10 (25.0); δ_(H) (400 MHz, CDCl₃) 1.00 (d, J=6.4 Hz, 3H), 1.21 (d, J=6.4 Hz, 3H), 2.12 (m, 2H), 2.48 (m, 1H), 2.61 (m, 1H), 2.78 (dd, J=11.6, 2.4 Hz, 1H), 2.83 (m, 3H), 3.42 (dd, J=13.6, 5.6 Hz, 1H), 3.79 (s, 3H), 5.15 (m, 2H), 5.40 (s, 1H), 5.85 (m, 1H), 6.64 (s, 1H), 6.86(m, 3H), 7.20 (m, 3H), 7.44 (d, J=8.0 Hz, 1H), 7.50 (d, J=8.0 Hz, 1H).

[0134] Its HCl salt: m.p. 97-104° C. (Ether); v_(max ()KBr) cm⁻¹ 3438, 1601 (s), 1260; Anal.Calcd.for C₂₅H₃₀N₂O₂.2HCl.0.50H₂O: C, 63.56; H, 7.04; N, 5.93. Found: C, 63.70; H, 6.68; N, 5.83.

Example 10 and 11

[0135] Preparation of (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Cyclopropylmethyl-2,5-dimethyl-1-piperazinyl)-2-benzofuranyl)anisole (Compounds 16 & 17)

[0136] The compounds of these Examples were prepared by following the synthesis procedure as described for Examples 2 and 3, except using cyclopropyl methyl iodide and substituting compound 3 for compound 13.

[0137] The first isomer, compound 16: GC-MS (R_(t)=14.87 min) 405.25 (M⁺+1, 2.3%), 404.25 (M⁺, 8.2), 362.20 (0.5), 349.15 (0.4), 320.20 (0.8), 292.20 (4.1), 291.10 (3.4), 265.10 (16.5), 237.10 (65.9), 194.10 (11.5), 167.20 (100), 140.20 (3.9), 124.15 (4.6), 98.15 (44.0); δ_(H) (400 MHz, CDCl₃) 0.05 (m, 2H), 0.46 (m, 2H), 0.80 (m, 1H), 0.92 (d, J=6.0 Hz, 3H), 1.21 (d, J=6.0 Hz, 3H), 2.01 (dd, J=12.8, 7.2 Hz, 1H), 2.17 (m, 2H), 2.35 (m, 1H), 2.64 (dd, J=13.2, 6.4 Hz, 1H), 2.66 (m, 1H), 2.72 (dd, J=12.0, 2.4 Hz, 1H), 3.04 (dd, J=11.2, 3.2 Hz, 1H), 3.75 (s, 3H), 5.50 (s, 1H), 6.58 (s, 1H), 6.79 (dd, J=8.0, 2.4 Hz, 1H), 7.01 (d, J=8.0 Hz, 1H), 7.09 (s, 1H), 7.20 (m, 3H), 7.41 (d, J=8.0 Hz, 1H), 7.51 (m, 1H); δ_(C-13) (100 MHz, CDCl₃) 3.2, 4.7, 7.4, 17.4, 17.7, 53.1, 54.5, 55.2, 56.0, 58.3, 59.2, 60.8, 106.8, 111.3, 112.0, 114.2, 120.6, 120.7, 122.6, 123.7, 128.0, 129.0, 141.4, 154.8, 155.2, 159.6.

[0138] Its HCl sa t: m.p. 162-164° C. (Ether); v_(max) (KBr) cm⁻¹ 3414, 1599, 1255; Anal.Calcd.for C₂₆H₃₂N₂O₂.2HCl.0.5H₂O: C, 64.19; H, 7.25; N, 5.76. Found: C, 64.43; H, 7.30; N, 5.78.

[0139] The second isomer, compound 17: GC-MS (R_(t)=15.17 min) 405.25 (M⁺+1, 2.2%), 404.25 (M⁺, 8.9), 362.10 (0.6), 349.15 (0.4), 320.10 (0.8), 292.10 (5.0), 291.10 (3.9), 265.10 (19.4), 237.10 (72.2), 194.10 (12.8), 167.20 (100), 140.10 (3.9), 124.15 (4.8), 98.15 (45.5); δ_(H) (400 MHz, CDCl₃) 0.08 (m, 2H), 0.48 (m, 2H), 0.82 (m, 1H), 0.97 (d, J=6.4 Hz, 3H), 1.25 (d, J=6.4 Hz, 3H), 2.10 (m, 2H), 2.28 (dd, J=11.2, 10.0 Hz, 1H), 2.49 (m, 1H), 2.62 (dd, J=13.2, 6.0 Hz, 1H), 2.63 (m, 1H), 2.83 (dd, J=11.2, 2.8 Hz, 1H), 3.02 (dd, J=11.2, 3.2 Hz, 1H), 3.78 (s, 3H), 5.43 (s, 1H), 6.64 (s, 1H), 6.87 (m, 3H), 7.21 (m, 3H), 7.45 (dd, J=7.6, 1.2 Hz, 1H), 7.50 (m, 1H); δ_(C-13) (100 MHz, CDCl₃) 3.3, 4.6, 7.4, 17.0, 17.6, 52.6, 55.2, 55.4, 55.6, 58.3, 60.3, 61.6, 105.7, 111.3, 112.5, 115.9, 120.5, 122.1, 112.5, 123.5, 128.4; 128.9, 137.3, 155.0, 158.3, 159.3.

[0140] Its HCl salt: m.p. 92-105° C. (Ether); v_(max) (KBr) cm⁻¹ 3398, 1599, 1257; Anal.Calcd.for C₂₆H₃₂N₂.2HCl.0.5H₂O: C, 64.19; H, 7.25; N, 5.76. Found: C, 64.38; H, 7.14; N, 5.73.

[0141] D.

[0142] I. Preparation of 6-Quinolinecarboxaldehyde

[0143] A mixture of 6-methylquinoline (5.72 g, 40.0 mmol) and selenium oxide (4.44 g, 40.0 mmol) was heated to 220° C. for 1 h. After cooling down the residue was dissolved in ethyl acetate (100 mL). The organic solution was washed with brine, dried over MgSO₄. Evaporation of solvents provided a solid, which was recrystalized from ether-hexane (1:1) mixture to give 6-quinolinecarboxaldehyde (3.45 g, 55%).

[0144] GC-MS (R_(t)=5.29 min) 157.15 (M⁺, 100%), 156.15 (92.2), 128.15 (62.9), 101.15 (16.0); δ_(H) (400 MHz, CDCl₃) 7.53 (m, 1H), 8.21 (m, 2H), 8.33 (m, 2H), 9.06 (m, 1H), 10.21 (s, 1H); δ_(C-13) (100 MHz, CDCl₃) 122.1, 126.6, 127.6, 130.7, 133.5, 134.2, 137.3, 150.8, 153.0, 191.3.

[0145] The compounds according to Examples 12-17 were synthesized as shown in Scheme 4 above.

[0146] II. Preparation of 3-methoxy-α-(6-(quinolinyl)benzyl Alcohol (Compound 18)

[0147] The compound 18 was prepared by following the synthesis procedure as described for compound 1, but substituting 1-naphtaldehyde for 6-quinolinecarboxaldehyde.

[0148] GC-MS (R_(t)=11.13 min) 265.10 (M⁺, 49.0%), 248.05 (2.3), 204.05 (9.7), 156.05 (37.6), 135.00 (100), 109.00 (43.5); δ_(H) (400 MHz, CDCl₃) 3.73 (s, 3H), 5.94 (s, 1H), 6.78 (d, J=8.4 Hz, 1H), 6.95 (m, 2H), 7.22 (m, 1H), 7.31 (m, 1H), 7.61 (d, J=8.4 Hz, 1H), 7.83 (s, 1H), 7.95 (d, J=8.4 Hz, 1H), 8.07 (d, J=8.0 Hz, 1H), 8.73 (m, 1H); δ_(C-13) (100 MHz, CDCl₃) 55.2, 75.7, 112.3, 113.1, 119.1, 121.2, 124.6, 128.5, 129.4, 129.6, 136.3, 142.1, 145.2, 147.6, 150.1, 159.8.

[0149] III. Preparation of 3-methoxy-α-(6-quinolinyl)benzyl Chloride (Compound 19)

[0150] The compound 19 was prepared by following the synthesis procedure as described for compound 2, but substituting compound 1 for compound 18.

[0151] Used directly in the next step: δ_(H) (400 MHz, CDCl₃) 3.73 (s, 3H), 5.98 (s, 1H), 6.8-8.2 (m, 9H), 8.80 (s, 1H).

Example 12 and 13

[0152] Preparation of (±)-trans-1-(3-methoxy-α-(6′-quinolinyl)benzyl)-2,5-dimethylpiperazine (Compounds 20 & 21)

[0153] The compounds of these Examples were prepared by following the synthesis procedure as described for compound 3, but substituting compound 2 for compound 19.

[0154] GC-MS (R_(t)=14.91 min) 361.20 (M⁺, 0.8%), 332.15 (0.3), 306.15 (0.6), 302.15 (14.4), 277.15 (52.5), 248.05 (100), 233.00 (10.6), 204.05 (17.1), 176.05 (2.7), 151.05 (1.4), 142.10 (1.8), 113.10 (19.9).

[0155] The first isomer, compound 20: δ_(H) (400 MHz, CDCl₃) 1.06 (d, J=6.4 Hz, 3H)′ 1.24 (d, J=6.4 Hz, 3H), 1.84 (dd, J=11.6, 9.2 Hz, 1H), 2.60 (m, 2H), 2.77 (m, 2H), 3.06 (m, 2H), 3.80 (s, 3H), 5.44 (s, 1H), 6.77 (s, 1H), 6.83 (d, J=8.0 Hz, 1H), 6.88 (dd, J=8.0, 2.4 Hz, 1H), 7.31 (m, 1H), 7.37 (m, 1H), 7.82 (s, 1H), 7.84 (m, 1H), 8.03 (d, J=8.8 Hz, 1H), 8.09 (d, J=8.8 Hz, 1H), 8.87 (m, 1H).

[0156] Compound 21 (a mixture of two isomers, ˜25% compound 20): δ_(H) (400 MHz, CDCl₃) 1.20 (m, 6H), 2.05 (m, 1H), 2.73 (m, 2H), 2.87 (m, 1H), 3.13 (m, 2H), 3.73 & 3.76 (s, 3H), 5.38 (s, 1H), 6.38 (brs, NH), 6.70-8.15 (m, 9H), 8.84 (m, 1H).

Example 14

[0157] Preparation of (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-6-quinolinyl)anisole (Compound 22)

[0158] The compound of this Example was prepared by following the synthesis procedure as described for Examples 2 and 3, but substituting compound 3 for compound 20.

[0159] GC-MS (R_(t)=17.22 min) 401.25 (M⁺, 0.3%), 360.20 (0.3), 331.10 (0.2), 303.20 (1.7), 276.10 (4.5), 248.10 (17.2), 233.10 (4.5), 204.10 (8.0), 176.10 (1.3), 153.20 (100), 126.20 (5.4); δ_(H) (400 MHz, CDCl₃) 1.0 (d, J=6.4 Hz, 3H), 1.21 (d, J=6.4 Hz, 3H), 1.99 (m, 1H), 2.20 (m, 1H), 2.56 (m, 1H), 2.66 (m, 1H), 2.71 (m, 1H), 2.85 (m, 1H), 2.90 (m, 1H), 3.37 (dd, J=13.2, 4.0 Hz, 1H), 3.78 (s, 3H), 5.17 (m, 2H), 5.35 (s, 1H), 5.87 (m, 1H), 6.82 (m, 3H), 7.26 (t, J=7.6 Hz, 1H), 7.36 (m, 1H), 7.81 (s, 1H), 7.88 (d, J=8.8 Hz, 1H), 8.03 (d, J=8.8 Hz, 1H), 8.09 (d, J=7.6 Hz, 1H), 8.87 (m, 1H); δ_(C-13) (100 MHz, CDCl₃) 15.7, 16.4, 52.0, 53.7, 55.2, 55.5, 56.8, 58.9, 65.9, 112.1, 116.3, 117.8, 120.9, 122.5, 126.5, 127.9, 128.9, 129.0, 130.2, 134.8, 136.0, 139.2, 141.1, 147.6, 150.0, 159.5.

[0160] Its HCl salt m.p. 128-140° C. (Ether); v_(max) (KBr) cm⁻¹ 3376, 1596, 1263; Anal.Calcd.for C₂₆H₃₁N₃O.2.30HCl.0.1H₂O: C, 64.10; H, 6.93; N, 8.62. Found: C, 64.08; H, 6.92; N, 8.35.

Example 15

[0161] Preparation of (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-6-(quinolinyl)anisole (Compound 23)

[0162] The compound of this Example was prepared by following the synthesis procedure as described for Examples 2 and 3, but substituting compound 3 for compound 21.

[0163] GC-MS (R_(t)=17.21 min) 401.35 (M⁺, 0.4%), 360.30 (0.2), 331.20 (0.2), 303.20 (1.6), 276.10 (4.8), 248.10 (17.3), 233.10 (4.4), 204.10 (8.1), 176.10 (1.3), 153.20 (100), 126.20 (5.6); δ_(H) (400 MHz, CDCl₃) 1.01 (d, J=6.0 Hz, 3H), 1.21 (d, J=6.0 Hz, 3H), 1.95 (m, 1H), 2.16 (m, 1H), 2.56 (m, 1H), 2.66 (m, 1H), 2.74 (m, 1H), 2.80 (m, 1H), 2.87 (m, 1H), 3.30 (dd, J=13.6, 5.6 Hz, 1H), 3.77 (s, 3H), 5.13 (m, 2H), 5.34 (s, 1H), 5.82 (m, 1H), 6.77 (dd, J=8.0, 2.4 Hz, 1H), 6.99 (d, J=7.6 Hz, 1H), 7.11 (s, 1H), 7.21 (d, J=8.0 Hz, 1H), 7.38 (dd, J=8.4, 4.0 Hz, 1H), 7.59 (d, J=8.4 Hz, 1H), 7.66 (s, 1H), 8.03 (d, J=8.8 Hz, 1H), 8.11 (d, J=8.4 Hz, 1H), 8.88 (m, 1H); δ_(C-13) (100 MHz, CDCl₃) 15.3, 16.2, 51.9, 53.4, 55.2, 55.3, 56.8, 58.5, 66.1, 111.8, 114.0, 117.6, 120.6, 121.1, 127.9, 128.3, 128.9, 129.1, 131.4, 134.9, 136.0, 137.1, 144.1, 147.7, 150.2, 159.6.

[0164] Its HCl salt: m.p. 177-182° C. (Ether); v_(max) (KBr) cm⁻¹ 3405, 1597, 1260; Anal.Calcd.for C₂₆H₃₁N₃₀.2.80HCl: C, 62.01; H, 6.76; N, 8.34. Found: C, 61.98; H, 6.77; N, 8.03.

Example 16 and 17

[0165] Preparation of (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Cyclopropylmethyl-25-dimethyl-1-piperazinyl)-4-quinolinyl)anisole (Compounds 24 & 25)

[0166] The compounds of these Examples were prepared by following the synthesis procedure as described for Examples 2 and 3, but substituting allylbromide for cyclopropylmethylioidide.

[0167] The first isomer, compound 24: GC-MS (R_(t)=20.77 min) 415.25 (M⁺, 3.8%), 344.15 (2.4), 302.10 (9.5), 276.10 (58.8), 248.15 (79.1), 233.10 (17.2), 204.10 (29.4), 176.10 (4.2), 167.15 (100), 138.15 (14.2), 112.15 (47.0); δ_(H) (400 MHz, CDCl₃) 0.10 (m, 2H), 0.51 (m, 2H), 0.86 (m, 1H), 0.97 (d, J=6.4 Hz, 3H), 1.25 (d, J=6.4 Hz, 3H), 1.98 (dd, J=11.2, 8.8 Hz, 1H), 2.14 (dd, J=13.2, 6.4 Hz, 1H), 2.32 (dd, J=10.8, 5.6 Hz, 1H), 2.58 (m, 2H), 2.66 (dd, J=11.6, 2.8 Hz, 1H), 2.73 (m, 1H), 3.07 (dd, J=11.2, 3.2 Hz, 1H), 3.78 (s, 3H), 5.39 (s, 1H), 6.79 (s, 1H), 6.84 (m, 2H), 7.26 (t, J=8.0 Hz, 1H), 7.35 (dd, J=8.4, 4.0 Hz, 1H), 7.83 (s, 1H), 7.89 (d, J=8.8 Hz, 1H), 8.03 (d, J=9.2 Hz, 1H), 8.09 (d, J=8.0 Hz, 1H), 8.86 (dd, J=4.0, 2.0 Hz, 1H); δ_(C-13) (100 MHz, CDCl₃) 3.4, 4.4, 7.6, 16.2, 16.9, 52.1, 53.8, 55.2, 55.6, 58.5, 59.7, 65.6, 112.0, 116.3, 120.9, 122.6, 126.5, 127.9, 128.8, 129.0, 130.2, 136.0, 139.1, 141.1, 147.6, 149.9, 159.4.

[0168] Its HCl salt: m.p. 127-157° C. (Ether); v_(max) (KBr) cm⁻¹ 13402, 1596, 1262; Anal.Calcd.for C₂₇H₃₃N₃O.3HCl.0.75H₂O: C, 60.23; H, 7.02; N, 7.80. Found: C, 60.49; H, 7.00; N, 7.73.

[0169] The second isomer, compound 25: GC-MS (R_(t)=20.73 min) 415.25 (M⁺, 3.2%), 344.05 (2.3), 302.10 (7.7), 276.10 (48.5), 248.15 (69.6), 233.10 (15.7), 204.10 (25.8), 176.10 (3.7), 167.15 (100), 138.15 (12.2), 112.15 (46.8); δ_(H) (400 MHz, CDCl₃) 0.17 (m, 2H), 0.56 (m, 2H), 0.97 (m, 1H), 1.11 (brs, 3H), 1.27 (brs, 3H), 2.24 (m, 1H), 2.38 (m, 1H), 2.51 (m, 1H), 2.61 (m, 1H), 2.87 (m, 3H), 3.13 (m, 1H), 3.77 (s, 3H), 5.34 (s, 1H), 6.78 (d, J=8.0 Hz, 1H), 6.98 (d, J=8.0 Hz, 1H), 7.08 (s, 1H), 7.22 (t, J=8.0 Hz, 1H), 7.39 (dd, J=8.4, 4.4 Hz, 1H), 7.60 (d, J=8.4 Hz, 1H), 7.73 (s, 1H), 8.04 (d, J=8.8 Hz, 1H), 8.16 (d, J=8.4 Hz, 1H), 8.89 (d, J=4.0 Hz, 1H); δ_(C-13) (100 MHz, CDCl₃) 4.07, 4.37, 6.9, 14.8, 15.1, 51.4, 55.2, 56.2, 58.2, 60.3, 66.4, 111.8, 114.2, 120.6, 121.2, 128.0, 128.1, 129.2, 131.0, 136.0, 137.0, 143.8, 147.7, 150.3, 159.6.

[0170] Its HCl salt: m.p. 92-105° C. (Ether); v_(max) (KBr) cm⁻¹ 13345, 1596, 1259.

[0171] The compounds according to Examples 18-20 were synthesized as shown in Scheme 5 above.

[0172] E.

[0173] I. Preparation of 3-methoxy-α-(4-quinolinyl)benzyl Alcohol (Compound 26)

[0174] The compound 26 was prepared by following the synthesis procedure as described for compound 1, but substituting 1-naphtaldehyde for 4-quinolinecarboxaldehyde.

[0175] GC-MS (R_(t)=10.81 min) 266.10 (M⁺+1, 11.8%), 265.10 (M⁺, 61.0), 248.05 (6.1), 232.00 (6.2), 216.05 (4.7), 204.00 (10.5), 191.05 (2.0), 176.00 (3.8), 156.00 (13.9), 135.10 (100), 129.10 (86.6), 109.10 (68.2). 102.10 (25.5): δ_(H) (400 MHz. CDCl₃) 3.67 (s, 3H), 5.30 (brs, 1H), 6.41 (s, 1H), 6.76 (d, J=7.2 Hz, 1H), 6.90 (m, 2H), 7.18 (t, J=7.6 Hz, 1H), 7.38 (m, 1H), 7.56 (t, J=7.6 Hz, 1H), 7.62 (m, 1H), 7.92 (d, J=8.4 Hz, 1H), 8.00 (d, J=8.4 Hz, 1H), 8.64 (dd, J=4.4, 1.2 Hz, 1H); δ_(C-13) (100 MHz, CDCl₃) 55.1, 72.1, 113.0, 113.2, 118.5, 119.5, 123.9, 125.7, 126.5, 129.0, 129.5, 129.7, 143.8, 147.8, 149.1, 149.9, 159.7.

[0176] II. Preparation of 3-methoxy-α-(4-quinolinyl)benzyl Chloride (Compound 27)

[0177] The compound 27 was prepared by following the synthesis procedure as described for compound 2, but substituting compound 1 for compound 26.

[0178] Used directly in the next step: GC-MS (R_(t)=10.54 min) 285.10 (M⁺+2, 11.5%), 283.10 (M⁺, 33.10), 268.05 (0.2), 248.15 (100), 233.10 (37.0), 217.05 (27.2), 204.10 (45.5), 178.10 (5.9), 176.10 (11.5), 151.10 (5.7), 139.05 (2.1), 108.60 (11.0), 102.10 (17.4).

Example 18

[0179] Preparation of (±)-trans-1-(3-methoxy-α-(4-quinolinyl)benzyl)-2,5-dimethylpiperazine (Compound 28)

[0180] The compound of this Example was prepared by following the synthesis procedure as described for compound 3, but substituting compound 2 for compound 27.

[0181] GC-MS (R_(t)=13.96 min) 362.20 (M⁺+1, 1.4%), 361.20 (M⁺, 6.6), 306.10 (2.0), 302.15 (18.3), 277.15 (59.6), 248.15 (100), 233.10 (15.8), 204.10 (20.9), 176.10 (3.8), 151.00 (1.8), 143.15 (1.4), 113.15 (15.8); δ_(H) (400 MHz, CDCl₃) 0.92 (d, J=6.4 Hz, 3H), 1.12 (d, J=6.4 Hz, 3H), 1.82 (dd, J=11.6, 10.0 Hz, 1H), 2.52 (brs, 1H), 2.62 (dd, J=11.6, 2.8 Hz, 1H), 2.72 (m, 1H), 2.77 (m, 1H), 2.88 (m, 1H), 2.98 (dd, J=11.6, 2.0 Hz, 1H), 3.72 (s, 3H), 5.86 (s, 1H), 6.69 (s, 1H), 6.72 (d, J=8.0, 1H), 6.78 (dd, J=8.0, 2.4 Hz, 1H), 7.20 (t, J=8.0 Hz, 1H), 7.37 (t, J=8.0 Hz, 1H), 7.60 (t, J=8.0 Hz, 1H), 7.65 (d, J=4.4 Hz, 1H), 7.99 (d, J=8.8 Hz, 1H), 8.09 (d, J=8.0 Hz, 1H), 8.89 (d, J=4.4 Hz, 1H).

Example 19 and 20

[0182] Preparation of (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-25-dim ethyl-1-piperazinyl)-4-quinolinyl)anisole (Compounds 29 & 30)

[0183] The compounds of these Examples were prepared by following the synthesis procedure as described for Examples 2 and 3, but substituting compound 3 for compound 28.

[0184] The first isomer, compound 29: GC-MS (R_(t)=15.97 min) 401.15 (M⁺, 0.8%), 360.20 (0.8), 303.15 (3.3), 27615 (5.7), 248.05 (15.3), 217.05 (6.3). 204.10 (10.4), 176.00 (2.2), 153.20 (100), 126.10 (5.3), 98.10 (13.8); δ_(H) (400 MHz, CDCl₃) 0.96 (d, J=6.0 Hz, 3H), 1.14 (d, J=6.0 Hz, 3H), 2.01 (m, 1H), 2.16 (t, J=10.0 Hz, 1H), 2.47 (m, 1H), 2.59 (d, J=11.2 Hz, 1H), 2.86 (m, 2H), 2.95 (t, J=6.0 Hz, 1H), 3.36 (dd, J=13.6, 4.4 Hz, 1H), 3.72 (s, 3H), 5.15 (m, 2H), 5.77 (s, 1H), 5.85 (m, 1H), 6.74 (m, 3H), 7.17 (t, J=7.6 Hz, 1H), 7.38 (t, J=8.0 Hz, 1H), 7.60 (dd, J=7.2, 0.8 Hz, 1H), 7.73 (d, J=4.4 Hz, 1H), 8.00 (d, J=8.4 Hz, 1H), 8.08 (d, J=8.8 Hz, 1H), 8.90 (d, J=3.6 Hz, 1H); δ_(C-13) (100 MHz, CDCl₃) 15.9, 16.6, 53.8, 55.1, 55.5, 56.7, 59.4, 63.2, 112.0, 115.7, 117.7, 120.6, 121.9, 124.4, 126.0, 126.8, 128.6, 129.3, 130.1, 134.8, 140.3, 148.5, 148.6, 150.2, 159.5.

[0185] Its HCl salt: m.p. 158-166° C. (AcOEt-Ether); v_(max) (KBr) cm⁻¹ 3400, 1596, 1263; Anal.Calcd.for C₂₆H₃₁N₃O.3.0HCl.0.9H₂O: C, 59.24; H, 6.85; N, 7.97. Found: C, 59.31; H, 6.94; N, 7.80.

[0186] The second isomer, compound 30: GC-MS (R_(t)=16.19 min) 401.25 (M⁺, 0.5%), 386.20 (0.2), 360.20 (0.7), 331.10 (0.3), 303.15 (3.3), 276.15 (4.7), 248.15 (13.7), 233.10 (5.8), 217.05 (4.9), 204.10 (9.8), 176.10 (1.8), 153.20 (100), 126.20 (5.2), 98.10 (13.9); δ_(H) (400 MHz, CDCl₃); δ_(C-13) (100 MHz, CDCl₃).

[0187] Its HCl salt: m.p. 155-165° C. (AcOEt-Ether).

[0188] The compounds according to Examples 21-22 were synthesized as shown in Scheme 6 above.

[0189] F.

[0190] I. Preparation of (±)4-((α-Hydroxy)-4-chlorobenzyl)-N,N-diethylbenzamide (Compound 31)

[0191] 4-Formyl-N,N-diethylbenzamide (2.088 g, 10.1 mmol) was dissolved in 45 ml of anhydrous THF. The solution was cooled down to −78° C., followed by a dropwise addition of 10.1 ml (10.1 mmol) of a 1.0 M solution of 4-Chloro-phenylmagnesium bromide in ether. The mixture was warmed up to room temperature within 3 hours. Then 50 ml of a saturated NH₄Cl-solution was added and the mixture was extracted with ethyl acetate (3×30 ml). The combined organic layers were washed with water (2×30 ml) and brine (1×30 ml), dried (Na₂SO₄), filtered and the solvent was removed in vacuo. The residue was chromatographed on silica gel eluting with methanol:dichloromethane (1:125-3:125) to yiled the title compound as a colorless oil.

[0192] v_(max) (KBr)/cm⁻¹ 13329, 2977, 1595, 1461, 1289, 1094, 1051, 830: δ_(H) (400 MHz, CDCl₃) 1.09 (3H, br s), 1.21 (3H, br s), 3.22 (2H, br s), 3.33 (1H, d, J 3), 3.50 (2H, br s), 5.74 (1H, d, J 3), 7.22-7.34 (m, 8H);

[0193] II. Preparation of (±)4-((α-Chloro)-4-chlorobenzyl)-N,N-diethylbenzamide (Compound 32)

[0194] The compound 32 was prepared by following the synthesis procedure as described for compound 2, but substituting compound 1 for compound 31.

[0195] Used for the next step without further purification.

Example 21

[0196] Preparation of (±)4-((α-(1-Piperazinyl)-4-chlorobenzyl)-N,N-diethylbenzamide (Compound 33)

[0197] The compound of this Example was prepared by following the synthesis procedure as described for compound 3, but substituting compound 2 for compound 32.

[0198] m.p. 112-113° C. (from acetonitrile), v_(max) (KBr)/cm⁻¹ 3347, 2947, 2809, 1615, 1451, 1318, 1284, 1094, 836; δ_(H) (400 MHz, CDCl₃) 1.10 (3H, br s), 1.21 (3H, br s), 1.69 (1H, br s), 2.33 (4H, br s), 2.86-2.89 (4H, m), 3.24 (2H, br s), 3.51 (2H, br s), 4.22 (1H, s), 7.23-7.41 (8H, m); C₂₂H₂₈N₃OCl.0.3H₂O requires:

[0199] C, 67.52; H, 7.37; N, 10.74. Found: C, 67.68; H, 7.37; N, 10.73.

Example 22

[0200] Preparation of (±)4-((α-((4-Allyl)-1-piperazinyl))-4-chlorobenzyl)-N,N-diethylbenzamide.2HCl (Compound 34)

[0201] The compound of this Example was prepared by following the synthesis procedure as described for Examples 2 and 3, but substituting compound 3 for compound 33.

[0202] m.p. 147-163° C. (from ether), v_(max) (KBr)/cm⁻¹ 3418, 2974, 2355, 1626, 1435, 1286, 1092, 945, 812; δ_(H) (400 MHz. CDCl₃) 1.06 (3H, br s), 1.19 (3H, br s). 3.0-3.7 (14H, m), 5.4-5.6 (2H, m), 6.0-6.2 (1H, br m), 7.2-7.8 (9H, m); C₂₅H₃₄N₃O₀C₃ requires:

[0203] C, 60.18; H, 6.87; N, 8.42. Found: C, 60.48; H, 6.89; N, 8.31.

[0204] The compounds according to Examples 23-24 were synthesized as shown in Scheme 7 above.

[0205] G.

[0206] I. Preparation of (±)4-((α-Hydroxy)-2-naphtylmethyl)-N,N-diethylbenzamide (Compound 35)

[0207] The compound 35 was prepared by following the synthesis procedure as described for compound 1, but substituting 3-bromoanisole for 2-bromoanisole, and 1-naphtaldehyde for N,N-diethyl-4-carboxybenzamide.

[0208] v_(max) (KBr)/cm⁻¹ 3302, 2976, 1607, 1430, 1290, 1098, 813; δ_(H) (400 MHz, CDCl₃) 1.09 (3H, br s), 1.22 (3H, br s), 2.60 (1H, d, J 3), 3.24 (2H, br s), 3.52 (2H, br s), 6.00 (1H, d, J 3), 7.30-7.50 (7H, m), 7.76-7.88 (4H, m);

[0209] II. Preparation of (±)4-((α-Chloro)-2-naphtyl-methyl)-N,N-diethylbenzamide (Compound 36)

[0210] The compound 36 was prepared by following the synthesis procedure as described for Used for the next step without further purification.

Example 23

[0211] Preparation of (±)4-((α-(1-piperazinyl))-2-naphtylmethyl)-N,N-diethylbenzamide (Compound 37)

[0212] The compound of this Example was prepared by following the synthesis procedure as described for Example 1, but substituting compound 2 for compound 36.

[0213] m.p. 106-108° C. (from acetonitrile), v_(max) (KBr)/cm⁻¹ 3324, 3052, 2964, 2810, 2774, 1613, 1465, 1287, 1130, 1098; δ_(H) (400 MHz, CDCl₃) 1.07 (3H, br s), 1.19 (3H, br s), 1.89 (1H, br s), 2.40 (4H, br s), 2.89-2.92 (4H, m), 3.21 (2H, br s), 3.50 (2H, br s), 4.41 (1H, s), 7.24-7.84 (11H, 3m); C₂₆H₃₁N₃O.0.9H₂O requires:

[0214] C, 74.75; H, 7.91; N, 10.06. Found: C, 74.68; H, 7.56; N, 10.38.

Example 24

[0215] Preparation of (±)4-((α-((4-Allyl)-1-piperazinyl))-2-naphtylmethyl)-N,N-diethylbenzamide (Compound 38)

[0216] The compound of this Example was prepared by following the synthesis procedure as described for Examples 2 and 3, but substituting compound 3 for compound 37.

[0217] v_(max) (KBr)/cm⁻¹ 3053, 2968, 2805, 1629, 1426, 1288, 1141, 1095, 921, 817; δ_(H) (400 MHz, CDCl₃) 1.06 (3H, br s), 1.19 (3H, br s), 2.49 (6H, br s), 3.00 (2H, m), 3.20 (2H, br s), 3.49 (2H, br s), 4.41 (1H, s), 5.08-5.22 (2H, m), 5.78-5.92 (1H, m), 7.26-7.84 (11H, m); C₂₅H₃₄N₃OCl₃. 0.6H₂O requires:

[0218] C, 76.99; H, 8.07; N, 9.29. Found: C, 77.06; H, 8.09; N, 9.32%.

[0219] The compounds according to Examples 25-26 were synthesized as shown in Scheme 8 above.

[0220] H.

[0221] I. Preparation of (±)4-((α-Hydroxy)-4-xylyl)-N,N-diethylbenzamide (Compound 39)

[0222] The compound 39 was prepared by following the synthesis procedure as described for compound 31, but substituting 4-chlorophenylmagnesiumbromide for 4-toluylmagnesiumbromide.

[0223] v_(max) (KBr)/cm⁻¹ 3364, 2970, 1602, 1455, 1381, 1291, 1101, 1054, 802; δ_(H) (400 MHz, CDCl₃) 1.09 (3H, br s), 1.22 (3H, br s), 2.33 (3H, s), 2.55 (1H, br s), 3.24 (2H, br s), 3.52 (2H, br s), 5.78 (1H, d, J 3), 7.11-7.41 (8H, m);

[0224] II. Preparation of (±)4-((α-Chloro)-4-xylyl)-N,N-diethylbenzamide (Compound 40)

[0225] The compound 40 was prepared by following the synthesis procedure as described for compound 2.

[0226] Used for the next step without further purification.

Example 25

[0227] Preparation of (±)4-((α-(1-Piperazinyl))-4-xylyl)-N,N-diethylbenzamide (Compound 41)

[0228] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0229] m.p. 129-132° C. (from acetonitrile), v_(max) (KBr)/cm⁻¹ 3320, 2957, 2811, 1610, 1437, 1285, 1128, 1010, 838; δ_(H) (400 MHz, CDCl₃) 1.10 (3H, br s), 1.20 (3H, br s), 1.83 (1H, br s), 2.30 (3H, s), 2.34 (4H, br s), 2.86-2.89 (4H, m), 3.24 (2H, br s), 3.51 (2H, br s), 4.20 (1H, s), 7.06-7.46 (8H, 3m); C₂₃H₃₁N₃O requires:

[0230] C, 75.58; H, 8.55; N, 11.50. Found: C, 75.30; H, 8.54; N, 11.56.

Example 26

[0231] Preparation of (±)4-((α-((4-Allyl)-1-piperazinyl))-4-xylyl)-N,N-diethylbenzamide.2HCl (Compound 42)

[0232] The compound of this Example was prepared by following the synthesis procedure as described for Examples 2 and 3.

[0233] m.p. >160° C. dec. (from ether); v_(max) (KBr)/cm⁻¹ 3437, 2973, 2402, 1625, 1433, 1289, 1097, 944, 809; δ_(H) (400 MHz, CDCl₃, free base) 1.10 (3H, br s), 1.20 (3H, br s), 2.29 (3H, s), 2.35-2.60 (6H, m), 3.03 (2H, m), 3.24 (2H, br s), 3.52 (2H, br s), 4.22 (1H, s), 5.12-5.23 (2H, m), 5.81-5.93 (1H, m), 7.05-7.45 (8H, 3m);

[0234] The compounds according to Examples 27 were synthesized as shown in Scheme 9 above.

[0235] I.

[0236] I. Preparation of (±)4-((α-Hydroxy)-3-xylyl)-N,N-diethylbenzamide (Compound 43)

[0237] The compound 43 was prepared by following the synthesis procedure as described for compound 31, but substituting 4-chlorophenylmagnesiumbromide for m-toluylmagnesiumbromide.

[0238] v_(max) (KBr)/cm⁻¹ 3406, 2972, 1613, 1429, 1360, 1287, 1097, 1053, 789; δ_(H) (400 MHz, CDCl₃) 1.10 (3H, br s), 1.22 (3H, br s), 2.34 (3H, s), 2.55 (1H, d, J 3.5), 3.25 (2H, br s), 3.52 (2H, br s), 5.80 (1H, d, J 3), 7.12-7.42 (8H, m);

[0239] II. Preparation of (±)4-((α-Chloro)-3-xylyl)-N,N-diethylbenzamide (Compound 44)

[0240] The compound 44 was prepared by following the synthesis procedure as described for compound 2.

[0241] Used for the next step without further purification.

Example 27

[0242] Preparation of (±)4-((α-(1-piperazinyl))-4-xylyl)-N,N-diethylbenzamide.2HCl (Compound 45)

[0243] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0244] m.p. >130° C. dec. (from ether), v_(max) (Kbr)/cm⁻¹ 2971, 2805, 2715, 1624, 1434, 1289, 1096, 783; δ_(H) (400 MHz, CDCl₃, free base) 1.10 (3H, br s), 1.20 (3H, br s), 2.31 (3H, s), 2.35-2.45 (5H, m), 2.89-2.92 (4H, m), 3.25 (2H, br s), 3.51 (2H, br s), 4.19 (1H, s), 6.98-7.46 (8H, 4m);

[0245] The compounds according to Example 28 were synthesized as shown in Scheme 10 above.

[0246] J.

[0247] I. Preparation of (±)4-((α-Hydroxy)-cyclohexylmethyl)-N,N-diethylbenzamide (Compound 46)

[0248] The compound 46 was prepared by following the synthesis procedure as described for compound 31.

[0249] δ_(H) (400 MHz, CDCl₃) 0.85-2.0 (18H, m), 3.26 (2H, br s), 3.53 (2H, br s), 4.35-4.43 (1H, m), 7.28-7.36 (4H, m);

[0250] II. Preparation of (±)4-((α-Chloro)-cyclohexylmethyl)-N,N-diethylbenzamide (Compound 47)

[0251] The compound 47 was prepared by following the synthesis procedure as described for compound 2.

[0252] Used for the next step without further purification.

Example 28

[0253] Preparation of (±)4-((α-(1-piperazinyl))-cyclohexylmethyl)-N,N-diethylbenzamide (Compound 48)

[0254] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0255] m.p. 113-116° C. (from acetonitrile), v_(max) (KBr)/cm⁻¹ 3330, 2936, 2845, 1623, 1431, 1286, 1096, 823; δ_(H) (400 MHz, CDCl₃) 0.64-2.02 (18H, m), 2.18-2.40 (4H, m), 2.75-2.87 (4H, m), 3.06 (1H, d, J 8.8), 3.27 (2H, br s), 3.52 (2H, br s), 7.11 (2H, d, J 8.4), 7.29 (2H, d, J 8.4);

[0256] The compounds according to Examples 29 were synthesized as shown in Scheme 11 above.

[0257] K.

[0258] I. Preparation of (±)4-((α-Hydroxy)-3,4-dimethylbenzyl)-N,N-diethylbenzamide (Compound 49)

[0259] The compound 49 was prepared by following the synthesis procedure as described for compound 1.

[0260] δ_(H) (400 MHz, CDCl₃) 1.09 (3H, br s), 2.23 (6H, s), 2.85 (1H, d, J 3), 3.24 (2H, br s), 3.51 (2H, br s), 5.73 (1H, d, J 2), 7.03-7.12 (m, 3H), 7.26-7.39 (m, 4H);

[0261] II. Preparation of (±)4-((α-Chloro)-3,4-dimethylbenzyl)-N,N-diethylbenzamide (Compound 50)

[0262] The compound 50 was prepared by following the synthesis procedure as described for compound 2.

[0263] Used for the next step without further purification.

Example 29

[0264] Preparation of (±)4-((α-(1-Piperazinyl))-3,4-dimethylbenzyl)-N,N-diethylbenzamide (Compound 51)

[0265] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0266] v_(max) (KBr)/cm⁻¹ 3304, 2939, 2810, 1626, 1429, 1286, 1096, 846; δ_(H) (400 MHz, CDCl₃) 1.11 (3H, br s), 1.20 (3H, br s), 1.87 (1H, br s), 2.20 (3H, s), 2.22 (3H, s), 2.34 (4H, br s), 2.86-2.89 (4H, m), 3.25 (2H, br s), 3.51 (2H, br s), 4.15 (1H, s), 7.02-7.15 (3H, m), 7.26-7.30 (2H, m), 7.42-7.46 (2H, m);

[0267] The compounds according to Examples 30 were synthesized as shown in Scheme 12 above.

[0268] L.

[0269] I. Preparation of (±)4-(α-Hydroxy)-1-naphtylmethyl)-N,N-diethylbenzamide (Compound 52)

[0270] The compound 52 was prepared by following the synthesis procedure as described for compound 1.

[0271] δ_(H) (400 MHz, CDCl₃) 1.06 (3H, br s), 1.20 (3H, br s), 3.01 (1H, d, J 4), 3.21 (2H, br s), 3.49 (2H, br s), 6.47 (1H, d, J 4), 7.24-7.48 (7H, m), 7.55-7.58 (1H, m), 7.78-7.87 (2H, m), 7.98-8.01 (1H, m);

[0272] II. Preparation of (±)4-((α-Chloro)-1-naphtylmethyl)-N,N-diethylbenzamide (Compound 53)

[0273] The compound 53 was prepared by following the synthesis procedure as described for compound 2.

[0274] Used for the next step without further purification.

Example 30

[0275] Preparation of (±)4-((α-(1-piperazinyl))-1-naphtylmethyl)-N,N-diethylbenzamide (Compound 54)

[0276] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0277] v_(max) (KBr)/cm⁻¹ 3307, 3050, 2966, 2814, 1625, 1431, 1287, 1098, 843, 797; δ_(H) (400 MHz, CDCl₃) 1.04 (3H, br s), 1.17 (3H, br s), 2.14 (1H, br s), 2.40 (2H, br s), 2.46 (2H, br s), 2.83-2.95 (4H, m), 3.17 (2H, br s), 3.48 (2H, br s), 5.05 (1H, s), 7.22-7.28 (2H, m), 7.40-7.54 (5H, m), 7.70-7.94 (3H, m), 8.40-8.43 (1H, m);

[0278] Piperazine Ring Modifications: General Experimental and Examples

[0279] The compounds according to Examples 31-42 were synthesized as shown in Scheme 13 below.

[0280] M.

[0281] I. Preparation of 2-Dimethyl-S-methyl-piperazine-3,5-dione (Compound 55)

[0282] N-t-Butoxycarbonyl-2-aminoisobutyric acid (5.0 g, 25 mmol) and D,L-alanine methylester hydrochloride (3.5 g, 25 mmol) was dissolved in dry dichloromethane (50 mL) and cooled to 0° C. Triethylamine (3.5 mL, 25 mmol) and then 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (4.8 g, 25 mmol) was added and the mixture was stirred at 0° C. until lumps dissolved. The reaction mixture was then left in the freezer 4 d at −20° C. The organic solution was washed with water, 1M citric acid (aq.), water, dried (Na₂SO₄) and evaporated in vacuo to give 6.0 g (83° C.) of coupling product. Most of the coupling product (5 g) was dissolved in formic acid (50 mL) and stirred 12 h at 25° C. The acid was removed in vacuo and the residue dissolved in 2-butanol and heated at reflux for 4 h. The solution was cooled to 0° C. and the crystals filtered off and dried in vacuo at 100° C. Yield 2.6 g of pure compound 55 (82%) which could be recrystallized from methanol, mp: >300° C. IR (Kbr) (cm−1): 3000 (br), 1680 (s) (C═O). ¹H NMR (D₂O): δ=4.75 (s, 2H, NH). 4.21 (q, 1H, CHMe), 1.50-1.42 (m, 9H, 3Me). C₇H₁₂N₂O₂ requires C, 53.83; H, 7.74; N, 17.94. Found C, 53.89; H, 7.90; N, 17.79.

[0283] II. Preparation of 2-Dimethyl-5-methyl-piperazine Dihydrochloride (Compound 56)

[0284] Compound 55 (2.2 g, 14 mmol) was dissolved on dry THF (120 mL). Lithium aluminum hydride (42 mL, 1M in THF) was added in small portions. When addition complete, the solution was heated at reflux over night The solution was allowed to cool then excess hydride was destroyed by dropwise addition of water (1.6 mL), NaOH (1.6 mL, 15% solution) and water (4.8 mL). The granular precipitate was filtered off and solvent evaporated in vacuo. The residue was dissolved in dichloromethane, dried (K₂CO₃) and evaporation of solvent in vacuo gave 1.5 g (84%). Treatment with excess HCl in ether gave the dihydrochloride compound 56 which could be recrystallized from methanol/ether mp: >300° C. IR (cm−1), KBr: 2760, 1570 (R₂NH₂+). MS (amine):128, 113, 84, 71, 58. ¹H NMR (D₂O+DSS): δ=2.70-2.50 (m, 5H, CH₂—N, CH—N), 1.14 (s, 3H, 1 Me), 1.00-0.94 (s+d, 6H, 2 Me). C₇H₁₆N₂×2HCl requires C, 41.80; H, 9.02; N, 13.93. Found C, 42.03; H, 9.24; N, 14.00.

Example 31

[0285] Preparation of 4-(4-(2-Dimethyl-5-methyl-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide Dihdrocloride (Compound 57)

[0286] 4-(Chloro-(3-methoxyphenyl)methyl)-N,N-diethylbenzamide (0.61 g, 2.0 mmol) and compound 56 (0.50 g, 3.9 mmol) was dissolved in dry acetonitrile (5 mL). Potassium carbonate (0.26 g, 2.0 mmol) was added and the mixture heated at reflux for 2 d. The solvent was removed in vacuo and the residue purified by flash chromatography on silica (CH₂Cl₂/MeOH/NH₃(aq.)), 98:1:1 to 95:5:1 to yield 0.65 g (79%). Treatment with excess of HCl in ether. filtering and drying crystals in vacuo over KOH gave the dihydrochloride compound 57, mp: 134-36° C. IR (HCl salt, KBr) (cm−1): 3400 (br, OH), 2900 (br, R₂NH₂+), 1600 (s, C═O or R₂NH₂+), 1283, 1038 (C—O). MS (amine) 3 peaks: 423, 353, 325, 296, 127. ¹H NMR: (amine, CDCl₃): δ=7.40-6.60 (m, 8H, Ar—H), 5.26, 5.25, 4.61 (3s, 1H, CHAr₂), 3.70 (s, 3H, MeO), 3.4, 3.2 (2 br. s, 4H, MeCH₂), 3.1-2.0 (m, 5H, piperazine-H), 1.3-0.9 (m, 15H, 5Me). C₂₆H₃₇N₃O₂×2HCl requires C, 62.89; H, 7.92; N, 8.46. Found C, 63.41; H, 8.38; N, 8.56.

Example 32

[0287] Preparation of 4-(4-(1-Allyl-2-dimethyl-5-methyl-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide Dihydrochloride (Compound 58)

[0288] Compound 57 (0.39 g, 0.92 mmol) was dissolved in dry acetonitrile (5 mL). Potassium carbonate (0.13 g, 0.92 mmol) and allyl bromide (90 μL, 1.02 mmol) was added. After 3 h at 25° C. the solvent was evaporated and the residue purified by flash chromatography on silica (CH₂Cl₂/MeOH), 98:2 to 95:5 to give a total of 0.39 g (92%). Treatment with excess of HCl in ether, filtering and drying crystals in vacuo over KOH gave the dihydrochloride, compound 58, mp: 105-21° C. IR (HCl salt, Kbr) (cm−1): 3400 (br, OH), 2500 (br, R₂NH₂+), 16200 (s) (C═O or R₂NH₂+), 1285, 1043 (C—O). ¹H NMR: (amine, CDCl₃): δ=7.50-6.60 (m, 8H, Ar—H), 5.70 (m, 1H, allyl-H), 5.00 (m, 2H, allyl-H), 4.70 (s, 1H, CHAr₂), 3.70 (s, 3H, MeO), 3.5+3.3 (2 br. s, 4H, MeCH₂), 3.0-1.9 (m, 7H, piperazine-H), 1.2-0.8 (m, 15H, 5Me). C₂₉H₄₁N₃O₂×2HCl requires C, 64.91; H, 8.08; N, 7.83. Found C, 65.70; H, 8.60; N, 8.29.

[0289] N.

[0290] I. Preparation of 4-Allyl-2-dimethyl-5-methyl-piperazine (Compound 59)

[0291] Compound 56 (0.14 g, 0.91 mmol) was dissolved in acetonitrile and allyl bromide (80 μL, 0.91 mmol) was added at 0° C. After 1 h another portion of allyl bromide was added. After 2 h the solvent was evaporated and the residue purified by flash chromatography on silica (CH₂Cl₂/MeOH), 95:5 to 80:20 to give the monoallyl compound 59, 116 mg (69%).

Example 33

[0292] Preparation of 4-(1-(4-Allyl-2-dimethyl-5-methyl-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide Dihydrochloride (Compound 60)

[0293] The compound of this Example was prepared by following the synthesis procedure as described for Example 3.

[0294] Mp: 125-30° C. IR (2HCl, KBr) (cm−1): 3430(br), 2978, 2480(br.), 1607, 1436, 1285. MS(free amine):366, 296, 167. ¹H NMR: (D₂O+DSS): δ=7.60-6.90 (m, 9H, Ar—H), 6.0-5.5 (m, 4H, allyl-H+Ar₂CH), 3.80 (2s, 3H, MeO), 4.0-3.7 (m, 11H, allyl-H, piperazine-H, amide-CH₂), 1.3-1.0 (m, 15H, piperazine-Me, amide-Me). Anal. calc. for C₂₉H₄₁N₃O₂×2HCl×2.9H₂O: C, 59.15; H, 8.35; N, 7.14. Found: C, 59.05; H, 8.00; N, 7.22.

Example 34

[0295] Preparation of 4-(1-(2-dimethyl-5-methyl-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide Dihydrochloride (Compound 61)

[0296] 56 (42 mg, 0.33 mmol) and potassium carbonate (46 mg, 0.33 mmol) was dissolved in water (2 mL) and di-t-butyl dicarbonate (79 mg, 0.36 mmol) was added. After stirring 1 h the solvent was evaporated in vacuo and the residue purified by chromatography on silica (CH₂Cl₂/MeOH), 90:10 to give 43 mg of the mono-N-Boc protected 55 which was dissolved in dry acetonitrile together with potassium carbonate (26 mg, 0.19 mmol) and 4 (Chloro-(3-methoxyphenyl)methyl)-N,N-diethylbenzamide (63 mg, 0.19 mmol). After heating 4 days at reflux, the solvent was removed in vacuo and residue purified by chromatography on silica (CH₂C₂/MeOH), 100:0, 95:5. Treatment with formic acid (5 mL) for 3 h, evaporation of solvent in vacuo and extraction of the residue with CH₂Cl₂/1M NaOH, drying of the organic phase (K₂CO₃) and evaporation of solvent in vacuo gave 27 mg (33%) of the free amine. Treatment with excess HCl in ether gave the dihydrochloride which was dissolved in water and freeze-dried., mp: 145-50° C. IR (2HCl, KBr) (cm−1): 3500-3400(br), 1601, 1442, 1285. MS(free amine): 423, 296, 325, 127. ¹H NMR: (CDCl₃): δ=7.4-6.6 (m, 8H, Ar—H), 5.39, 5.36 (2s, 1H, Ar₂CH), 3.75 (s, 3H, MeO), 3.5, 3.25 (2 br. s, 4H, amide-Me), 2.80, 2.50, 2.05 (3m, 5H, piperazine-H), 1.5 (br.s, 1H, N—H), 1.25-1.0 (br. m, 6H, amide-Me), 1.15 (s, 3H, Me), 0.90 (d, 3H, Me), 0.85 (s, 3H, Me). Calc. for C₂₆H₃₇N₃₀₂×2HCl×7.4H₂O: C, 49.58; H, 8.61; N, 6.67. Found: C, 49.61; H, 7.73; N, 6.56.

[0297] O.

[0298] I. Preparation of 4-(Phenyl-hydroxymethyl)-N,N-diethylbenzamide (Compound 62)

[0299] The compound 62 was prepared by following the synthesis procedure as described for compound 1.

[0300] MS: 282, 211, 165, 105. ¹H NMR: (CDCl₃): δ=7.38-7.20 (m, 9H), 5.80 (d, J=3.5 Hz, 1H), 3.5, 3.2 (2br.s, 4H), 1.2, 1.05 (2br. s, 6H).

[0301] II. Preparation of 4-(Chloro-phenyl-methyl)-N,N-diethylbenzamide (Compound 63

[0302] The compound 63 was prepared by following the synthesis procedure as described for compound 2.

[0303] GC-MS (2 peaks):296, 225, 165, 121. and 300, 266, 229, 195, 165. ¹H NMR: (CDCl₃): δ=7.45-7.20 (m, 9H), 6.09 (s, 1H), 3.4 (br. m, 4H), 1.1 (br. m, 6H).

Example 35

[0304] Preparation of 4-((1-piperazinyl)-benzyl)-N,N-diethylbenzamide Dihydrochloride (Compound 64)

[0305] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0306] Mp: 157-69° C. IR (amine, CDCl₃ in KBr cell) (cm−1): 3690, 3630, 1613, 1435, 1265. MS (free amine): 351, 306, 295, 266, 194, 165. ¹H NMR: (free amine, CDCl₃): δ=7.46-7.16 (m, 9H, Ar—H), 4.24 (s, 1H, CHAr₂), 3.5+3.2 (2 br. s, 4H, MeCH₂), 2.89 (m, 4H, piperazine-H), 2.36 (br. s, 4H, piperazine-H), 1.94 (br s, 1H, NH), 1.2+1.1 (2 br. s, 6H, 2Me). Anal. calc. for C₂₂H₂₉N₃O×2HCl×1.90H₂O, C, 57.61; H, 7.65; N, 9.16. Found C, 57.59; H, 7.66; N, 8.92.

Example 36

[0307] Preparation of 4-((4-Allyl-1-piperazinyl)-benzyl)-N,N-diethylbenzamide Dihydrochloride (Compound 65)

[0308] The compound of this Example was prepared by following the synthesis procedure as described for Examples 2 and 3.

[0309] Mp: 175-205° C. IR (amine, CDCl₃ in KBr cell) (cm−1): 3689, 1613, 1455, 1434, 1290, 1143. MS (free amine): 391, 165, 125. ¹H NMR: (free amine, CDCl₃): δ=7.42-7.12 (m. 9H, Ar—H), 5.81 (m, 1H, allyl-H), 5.10 (m, 2H, allyl-H), 4.23 (s, 1H, CHAr₂), 3.5+3.2 (2 br. s, 4H, MeCH₂), 3.00 (m, 2H, allyl-H), 2.6-2.4 (br. s, 8H, piperazine-H), 1.1 (2 br. s, 6H, 2Me). Anal. calc. for C₂₅H₃₅N₃O×2HCl×1.0H₂O, C, 62.23; H, 7.73; N, 8.71. Found C, 62.22; H, 7.49; N, 8.42.

[0310] P.

[0311] I. Preparation of 2-Hydroxymethyl-5-methyl-piperazine-3,5-dione (Compound 66)

[0312] (D,L)-N-t-Butoxycarbonyl-alanine (5.0 g, 26 mmol) was dissolved in methylene chloride (50 mL) with triethyl amine (8.1 mL), dried with 4 A molecular sieves and transfered to dry flask under nitrogen. i-Butyl chloroformate (3.8 mL, 29 mmol) was added at −10° C. The Solution was stirred 15 min, then D,L-serine methylester hydrochloride (4.1 g, 26 mmol) was added and the solution was allowed to reach 25° C. and stirred 12 h. Washing the solution with brine, drying (MgSO₄) and evaporating solvent in vacuo gave a solid which was treated with formic acid for 1 h. The acid was removed in vacuo and the residue dissolved in anhydrous 2-butanol (5 mL) and heated at reflux 2 days. The solvent was removed and the residue crystallized when treated with acetone to give 1 g of compound 66 (24%).

[0313] II. Preparation of 2-Hydroxymethyl-5-methyl-piperazine (Compound 67)

[0314] The compound 67 was prepared by following the synthesis procedure as described for compound 55.

[0315] II. Preparation of 2-(t-Butyldiphenylsilyloxy)methyl-5-methyl-piperazine (Compound 68)

[0316] Compound 67 (0.41 g, 3.1 mmol) was dissolved in dry DMF (5 mL). Chloro-t-butyldiphenylsilane (0.95 g, 3.4 mmol) and immidazole (0.47 g, 6.9 mmol) was added and stirring was continued 12 h. The product was extracted by adding ethyl acetate, brine and 1M NaOH and shaking. The organic phase was dried and evaporated in vacuo. Chromatography of the residue on silica (CH₂Cl₂/MeOH, 100:0, 95:5, 90:10 and 80:20) gave 0.39 g (34%) pure compound 68.

Example 37

[0317] Preparation of 4-(4-(2-Hydroxymethyl-5-methyl)piperazinyl-benzyl)-N,N-diethylbenzamide Dihydrochloride (Compound 69)

[0318] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0319] Mp: 145-50° C. IR (2HCl, KBr) (cm−1): 3300(br), 2700(br), 1612, 1446, 1382, 1296, 1080. MS(free amine):381, 218, 181, 91. ¹H NMR: (free amine, CDCl₃): δ=7.44-7.18 (m, 9H, Ar—H), 5.17, 5.14 (2s, 1H, ArCH₂), 3.75-2.60 (m, 12H, piperazine-H, amide-CH₂), 2.02 (m, 1H, piperazine-H), 1.30-1.05 (m, 9H, piperazine-Me+amide-Me). Anal. calc. for C₂₄H₃₃N₃O₂×2HCl×1.8H₂O: C, 57.55; H, 7.77; N, 8.39. Found: C, 57.05; H, 7.67; N, 8.19.

Example 38

[0320] Preparation of 4-((4-(2-Hydroxymethyl-5-methyl)piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide Dihydrochloride (Compound 70)

[0321] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0322] Mp: 185-90° C. IR (2HCl, KBr) (cm−1): 3500-2500(br), 1596, 1440, 1045. ¹H NMR: (free amine, CDCl₃): δ=7.40-6.60 (m, 8H, Ar—H), 5.05, 5.10 (2s, 1H, Ar₂CH). 3.70 (s, 3H, MeO), 3.8-2.5 (m, 12H, piperazine, amide CH₂) 1.2-1.0 (br. s, 9H, amide-Me, piperazine-Me).

Example 39

[0323] Preparation of 4-((4-(1-Allyl-2-hydroxymethyl-5-methyl)piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide Dihydrochloride (Compound 71)

[0324] The compound of this Example was prepared by following the synthesis procedure as described for Examples 2 and 3.

[0325] Mp: 125-30° C. IR (2HCl, KBr) (cm−1): 3400(br), 1603, 1445, 1285. MS(free amine): two, peaks: 310, 239, 135 and 312, 241, 135. ¹H NMR: (free amine, CDCl₃): δ=7.50-6.70 (m, 8H, Ar—H), 5.80, 5.20, 5.00 (3m, 3H, allyl-H), 4.0-2.3 (m, 14H, piperazine-H,allyl-H, amide-CH₂) 3.80 (s, 3H, MeO), 1.2 (br. s, 6H, amide-Me). Anal.calc. for C₂₅H₃₅N₃O₃×2HCl×3.7H₂O: C, 55.57; H, 8.06; N, 6.94. Found: C, 55.53; H, 7.82; N, 7.16.

[0326] Q.

[0327] I. Preparation of Methyl 3-(hydroxy-(2-naphtyl)methyl)phenyl Ether (Compound 72)

[0328] The compound 72 was prepared by following the synthesis procedure as described for compound 1.

[0329] MS: 264, 155, 135, 128, 109, 101. ¹H NMR: (CDCl₃): δ=7.90-6.78 (m, 1H, Ar—H), 5.98 (d, J=3.5 Hz, 1H, Ar₂H), 3.78 (s, 3H, MeO), 2.32 (d, J=3.5 Hz, 1H, OH).

[0330] II. Preparation of Methyl 3-(chloro-(2-naphtyl)methyl)phenyl Ether (Compound 73)

[0331] The compound 73 was prepared by following the synthesis procedure as described for compound 2.

[0332] GC-MS (2 peaks): 278, 247, 215, 171, 155, 135 and 282, 248, 247, 231, 215. ¹H NMR: (CDCl₃): δ=7.86-6.81 (m, 11H, Ar—H), 6.25 (s, 1H, Ar₂H), 3.76 (s, 3H, MeO).

[0333] III. Preparation of 4-Allyl-2-methylpiperazine (Compound 74)

[0334] 2-Methylpiperazine (0.4 g, 4 mmol) was dissolved in acetonitrile (5 mL) and allyl bromide (86 μL, 1 mmol) was added at 0° C. Stirring was continued at 0° C. for 1 h, then at 25° C. for 6 h. Evaporation of solvent in vacuo and chromatography on silica (CH₂O₂/MeOH, 80:20) gave 80 mg (57%) pure compound 74.

Example 40

[0335] Preparation of Methyl 3-((2-naphtyl)-(3-methyl-piperazinyl)methyl)phenyl Ether Dihydrochloride (Compound 75)

[0336] The compound of this Example was prepared by following the synthesis procedure as described for compound 3.

[0337] Mp: 170-74° C. IR (KBr) (cm−1): 3461, 2458, 1600, 1439, 1263, 1043. MS (amine): 386, 247, 215, 139, 112. ¹H NMR: (amine, CDCl₃): δ=7.84-6.66 (m, 11H, Ar—H), 4.33 (s, 1H, CHAr₂). 3.74, 3.73 (2s, 3H, MeO), 3.00-2.70 (m. 6H, piperazine-H). 1.95, 1.65 (2m, 2H, piperazine-H), 0.98-0.92 (2d, J=6.4 Hz, 3H, piperazine-Me). Anal. calc. for C₂₃H₂₆N₂₀×2HCl×1.8H₂O, C, 61.14; H, 7.05; N, 6.20. Found, C, 61.05; H, 6.48; N, 6.07.

Example 41

[0338] Preparation of Methyl 3-((2-naphtyl)-(4-allyl-2-methyl-piperazinyl)methyl)phenyl Ether Dihydrochloride (Compound 76)

[0339] The compound of this Example was prepared by following the synthesis procedure as described for Example 3.

[0340] Mp: 173-82° C. IR (KBr) (cm−1): 3430, 2500, 2355, 1601, 1436, 1265, 1047. MS (amine): 386, 274, 247, 215, 139, 125. ¹H NMR: (amine, CDCl₃): =7.86-6.66 (m, 11H, Ar—H), 5.82 (m, 1H, allyl-H), 5.12 (m, 2H, allyl-H), 4.95 (br. s, 1H, CHAr₂), 3.76, 3.75 (2s, 3H, MeO), 3.04-2.32 (m, 9H, piperazine-H), 1.15-1.11 (2d, 3H, Me). Anal. calc. for C₂₆H₃₂N₂O×2HCl×0.4H₂O, C, 66.92; H, 7.08; N, 6.00. Found C, 67.03; H, 7.09; N, 5.88.

Example 42

[0341] Preparation of 4-((4-Acetyl-1-piperazinyl)benzyl)-N,N-diethylbenzamide Hydrochloride (Compound 77)

[0342] The free amine of compound 64 (100 mg, 0.28 mmol) was dissolved in methylene chloride (5 ml), cooled to 0° C. Triethyl amine (43 mL 0.31 mmol) was added and then acetyl chloride (22 μl, 0.31 mmol) was added dropwise. After 10 min, the solution was washed with potassium carbonate (10%), dried (K₂CO₃) and evaporated in vacuo. The residue was purified by chromatography on silica (CH₂Cl₂/MeOH/NH₃, 95:5:0.5) to give 116 mg of compound 77 (−100%).

[0343] Mp: 140-50° C. IR (KBr) (cm−1): 3480(br), 2987, 2500(br), 1623, 1429, 1285, 1245. MS (free amine): 393, 267, 165, 127. ¹H NMR: (free amine, CDCl₃): δ=7.46-7.18 (m, 9H, Ar—H), 4.25 (s, 1H, CHAr₂), 3.70-3.15 (m, 8H, amide-CH₂, piperazine-H), 2.36 (m, 4H, piperazine-H), 2.05 (s, 3H, MeCO), 1.15 (br. m, 6H, amide-Me). Anal. calc. for C₂₄H₃₁N₃O₂×1HCl×0.80H₂O, C, 64.87. H, 7.62; N, 9.46. Found C, 65.01; H, 7.76; N, 9.42.

[0344] Diethylbenzamide Replacements Etch

[0345] The compounds according to Examples 43-48 were prepared as shown in Scheme 14 below.

[0346] R.

[0347] I. Preparation of 4-((4-t-Butoxycarbonyl-1-piperazinyl)-benzyl)-benzoic Acid (Compound 78)

[0348] Compound 64 (6.0 g, 17 mmol) was dissolved in 6N hydrochloric acid and heated at 120° C. for 3 days. The solution was then neutralized with aquous NaOH (−12 g). The solution was concentrated to 100 mL, mixed with THF (100 mL) and di-t-butyl dicarbonate (3.7 g, 17 mmol) added dissolved in THF (50 mL). After stirring 1 h at 25° C., the aquous phase was acidified with 1M citric acid and extracted two times with ethyl acetate. The organic phase was dried (K₂CO₃) and evaporated, and the residue purified by chromatography on silica (EtOAc/heptane/AcOH, 10:90:0 to 66:33:1) to give a total of 3.85 g (57%) of compound 78.

Example 43

[0349] Preparation of 4-((1-piperazinyl)-benzyl)-benzoic Acid Dihydrochloride (Compound 79)

[0350] Compound 78 (150 mg, 0.38 mmol) was treated with excess HCl in acetic acid 1 h. Acid removed in vacuo and residue dissolved in methanol and precipitated by addition of ether. The precipitate was dried in vacuum at 100° C. Mp: 172-80° C. IR (KBr) (cm−1): 3000(br), 1700, 1606, 1454. ¹H NMR: (DMSO-d₆): δ=12.85 (s, 1H, CO₂H), 8.95 (s, 2H, NH), 7.92-7.20 (m, 9H, Ar—H), 4.56 (s, 1H, Ar₂CH), 3.33 (s, 8H, piperazine-H). Anal. calc. for C₁₈H₂₀N₂O₂×2HCl, C, 58.54; H, 6.00; N, 7.59. Found: C, 59.9; H, 6.47; N, 7.88.

Example 44 and 45

[0351] Preparation of Methyl 4-((4-t-butoxycarbonyl-1-piperazinyl)-benzyl)benzoate (Compound 80) and Methyl 4-((1-piperazinyl)-benzyl)benzoate Dihydrochloride (Compound 81)

[0352] Compound 78 (0.15 g, 0.38 mmol) and cesium carbonate (0.25 g, 0.76 mmol) was mixed in DMF (2 mL) and methyl iodide (72 μL, 1.1 mmol) was added. After 2 h at 25° C., potassium carbonate (10%, aq.) and the solution was extracted with ethyl acetate. After evaporation of solvent in vacuo, the residue was purified by chromatography on silica (EtOAc/heptane, 30:70) to yield 0.13 g (87%) of the methyl ether, compound 80. Boc-deprotection was acheived by treatment with excess HCl in methanol at 50° C. The solvent was removed and the residue was purified again on silica The dihydrochloride, compound 81 (35 mg), was prepared according to previous methodology. Mp: 185-95° C. IR (KBr) (cm−1): 3400(br), 270((br), 1720, 1612, 1430, 1285, 1190, 1112. MS (EI, free amine): 310, 265, 225, 206, 165. ¹H NMR: (D₂O/CD₃OD+DSS): δ=8.20-7.34 (m, 9H, Ar—H), 5.03 (s, 1H, CHAr₂), 3.89 (s, 3H, MeO), 3.42 (m, 4H, piperazine-H), 3.08 (m, 4H, piperazine-H). Anal. calc. for C₁₉H₂₂N₂O₂×2HCl×1H₂O. C, 56.86; H, 6.53; N, 6.98. Found C, 56.82; H, 6.54; N, 7.00.

[0353] S.

[0354] I. Preparation of 4-((1-[)piperazinyl)-benzyl)benzamide Dihydrochloride (Compound 83)

[0355] Compound 78 (0.11 g, 0.28 mmol) was dissolved in dry methylene chloride/THF, 1:1 (5 mL) and cooled to −20° C. Triethylamine (78 μL, 0.56 mmol) was added and then i-butyl chloroformate (37 μL, 028 mmol). After 10 min, ammonia in methylene chloride (0.51 mL, 1.1M, 0.56 mmol) was added and the temperature was allowed to rise slowly to 25° C. After 3 h, the solvent was removed in vacuo and the residue was purified by chromatography on silica (CH₂Cl₂/MeOH/NH₃, 95:5:1 and 90:10:1) to give 70 mg (62%). Treatment with HCl in methanol 3 h at 50° C., removal of solvent in vacuo and chromatography on silica (CH₂Cl₂/MeOH/NH₃, 90:10:1 and 80:20:1) gave the free amine which was converted to the dihydrochloride salt 82. Mp: 192-200° C. IR (KBr) (cm−1): 3939(br), 3184(br), 2700(br), 1665, 1610, 1565, 1426. MS (amine): 295, 250, 210, 165, 152. ¹H NMR: (amine, CD₃OD): δ=7.96-7.22 (m, 9H, Ar—H), 4.93 (s, 2H, NH), 4.40 (s, 1H, Ar₂CH), 2.94+2.46 (2m, 8H, piperazine-H). Anal. calc. for C₁₈1H₂₁N₃O×2HCl×1.1H₂O, C, 55.70; H, 6.54; N, 10.83. Found C, 55.83; H, 6.76, N, 10.75.

Example 46

[0356] Preparation of 4-((1-piperazinyl)-benzyl)-N-ethylbenzamide Hydrochloride (Compound 83)

[0357] The compound of this Example was prepared by following the synthesis procedure as described for compound 82, but substituting ammonia for ethylamine.

[0358] Mp: 180-85° C. IR (KBr) (cm−1): 3331(br), 2700(br), 1640, 1545, 1440, 1308. MS: (EI, amine) 323, 278, 267, 238, 195, 165. ¹H NMR: (amine, CD₃OD): δ=7.84-7.14 (m, 9H, Ar—H), 4.9 (br. s, NH), 4.45 (s, 1H, Ar₂CH), 3.40 (m, 2H, ethyl-CH₂), 3.25, 2.65 (2m, 8H, piperazine-H), 1.20 (m, 3H, ethyl-Me).

Example 47

[0359] Preparation of 4-(1-piperazinyl-benzyl)-benzonitrile Dihydrochloride (Compound 84)

[0360] Compound 82 (45 mg, 0.11 mol) was dissolved in dry THF (2 mL) and cooled to 0° C. Pyridine (36 μL, 0.44 mg) and trifluoroacetic anhydride (3 mL, 0.22 mmol) was added and stirring was continued for 1 h at 25° C. Water was added and the solution was extracted with ethyl acetate. The organic phase was washed with dilute NaHCO₃ (aq), dried (K₂CO₃) and evaporated in vacuo. The residue was treated with HCl in methanol 3 h at 50° C. Removal of solvent in vacuo and chromatography on silica (CH₂Cl₂/MeOH/NH₃, 90:10:1) of residue gave 15 mg (49%). Treatment with excess HCl in ether/methanol gave the dihydrochloride compound 84 which was precipitated, dissolved in water and freeze-dried. Mp: 141-45° C. IR (KBr) (cm−1): 3400(br), 2700(br), 2230, 1434. MS (free amine): 277, 232, 192, 165. ¹H NMR: (free amine, CDCl₃): δ=7.58-7.18 (m, 9H, Ar—H), 4.27 (s, 1H, CHAr₂) 2.89, 2.35 (2m, 8H, piperazine-H), 1.70 (s, NH). Anal. calc. for C₁₈H₁₉N₃×2HCl×1H₂O, C, 58.70; H, 6.29; N, 11.41. Found C, 58.88; H, 6.46; N, 11.24.

Example 48

[0361] Preparation of 4-(1-piperazinyl-benzyl)-acetophenone Dihydrochloride (Compound 85)

[0362] Compound 78 (0.20 g, 0.50 mmol) was dissolved in dry THF (5 mL) and cooled to 0° C. under nitrogen. Methyl lithium (3.1 mL, 0.8M in ether, 2.5 mmol) was added during 1 min and stirring was continued for 2 h. Chlorotrimethylsilane (0.63 mL, 5.0 mmol) was added and the temperature was allowed to reach 25° C., then ammonium chloride (aq) was added. The organic phase was decanted off, evaporated and the residue purified by chromatography on silica (CH₂Cl₂/MeOH/NH₃, 95:5:1) to give 0.11 g (75%) of ketone without Boc-group. The dihydrochloride salt, compound 85 was prepared by treatment with excess HCl in ether. Mp: 175-85° C. IR (KBr) (cm−1): 3400(br), 2700(br), 1680, 1607, 1424, 1269. MS (EI, free amine): 294, 249, 209, 165. ¹H NMR: (free amine, CDCl₃): =7.77-7.04 (m, 9H, Ar—H), 4.22 (s, 1H, CHAr₂), 2.92 (m, 4H, piperazine-H), 2.43 (s, 3H, MeCO), 2.40 (m, 4H, piperazine-H).

[0363] Anal. calc. for C₁₉H₂₂N₂O×2HCl×1.6H₂O, C, 57.61; H, 6.92; N, 7.07. Found C, 57.54; H, 6.75; N, 6.91.

[0364] The compounds according to Example 49 were synthesized as shown in Scheme 15 above.

[0365] T.

[0366] I. Preparation of 4-benzoyl-N-t-butoxylcarbonylpiperidine (Compound 86)

[0367] A mixture of 4-benzoylpiperidine hydrochloride (6.77 g, 30.0 mmol), di-tert-butyldicarbonate (7.2 g, 33.0 mmol) and KHCO₃ (6.0 g, 60 mmol) in H₂O-THF (50/20 mL) was refluxed for 1 h. The reaction mixture was ex d with ethyl acetate (2×100 mL). The combined organic layers were washed with brine, dried over MgSO₄. Removal of solvents gave 4-benzoyl-N-t-butoxylcarbonyl-piperidine (8.54 g, 98%); δ_(H) (400 MHz, CDCl₃) 1.47 (s, 9H), 1.70 (m, 2H), 1.83 (m, 2H), 2.91 (m, 2H), 3.42 (m, 2H), 4.18 (brs, 2H), 7.46 (m, 2H), 7.56 (m, 1H), 7.93 (m, 2H).

[0368] II. Preparation 4-(α-Hydroxy-α-(4-N-t-butoxycarbonylpiperidinyl)-benzyl)-N,N-diethylbenzamide (Compound 87)

[0369] To a solution of 4-iodo-N,N-diethylbenzamide (3.03 g, 10.0 mmol) and TMEDA (1.28 g, 11.0 mmol) in dry THF (30 mL) was added t-butylithium (10.0 mL, 1.7 M, 17.0 mmol) at −78° C. After 10 min, 4-benzoyl-N-t-butoxylcarbonylpiperidine (2.89 g, 10.0 mmol) in THF (5 mL) was dropwise added. The reaction mixture was warned to r.t. and then quenched with aqueous NH₄Cl solution and extracted with ethyl acetate (2×100 mL). The combined organic layers were washed with ne, dried over MgSO₄. Removal of solvents gave a crude product, which was purified by silica gel column eluting with MeOH—CH₂Cl₂ (0:100→2:98) to provide 4-(α-hydroxy-α-(4-N-t-butoxycarbonylpiperidinyl)benzyl)-N,N-diethylbenzamide (MTL 0327, 2.60 g, 56%): m.p.: 100-103° C. (CH₂Cl₂): v_(max) (KBr) cm⁻¹ 3426, 2973, 1687, 1618, 1428, 1289, 1168; δ_(H) (400 z, CDCl₃) 1.08 (brs, 3H), 1.20 (brs, 3H), 1.30 (m, 4H), 1.41 (s, 9H), 2.50 (t, J=11.2 Hz, 1H), 2.66 (m, 2H), 2.86 (s, OH), 3.22 (brs, 2H), 3.50 (brs, 2H), 4.09 (brs, 2H), 7.18 (m, 1H), 7.26 (m, 4H), 7.45 (m, 4H); δ_(C-13) (100 MHz, CDCl₃) 12.8, 14.1, 26.2, 28.3, 39.1, 43.2, 44.3, 53.3, 79.2, 79.4, 125.75, 125.79, 126.2, 126.6, 128.1, 135.1, 145.3, 146.8, 154.6, 1710.0.

Example 49

[0370] Preparation 4-((α-4-piperidinyl)-benzyl)-N,N-diethylbenzamide (Compound 88)

[0371] To a solution of 4-(α-hydroxy-x 4-N-t-butoxylcarbonylpiperidinyl)benzyl)-N,N-diethylbenzamide (466 mg, 1.0 mmol) and triethylsilane (232 mg, 2.0 mmol) in dry dichloromethane (10 mL) was added trifluoroacetic acid (10.0 mL) at r.t. After 30 min at r.t., more triethylsilane (232 mg, 2.0 mmol) was added. The reaction mixture was stirred for 14 h at r.t, and then condensed. The residue was dissolved in AcOEt (100 ml). The resulting solution was washed with 1 N NaOH solution, aqueous NH₄Cl solution and brine, dried over MgSO₄. Removal of solvents gave a crude product, which was purified by silica gel column eluting with NH₄OH (1 N)-MeOH—CH₂Cl₂ (2.5:15:82.5) to provide 4-((α-4-piperidinyl)benzyl)-N,N-diethylbenzamide (245 mg, 70%): m.p.: 160-162° C. (CH₂Cl₂); v_(max) (KBr) cm⁻¹ 3325, 2937, 1613, 1461, 1283, 1095; δ_(H) (400 MHz, CDCl₃) 1.05 (brs, 3H), 1.07 (m, 2H), 1.19 (brs, 3H), 1.53 (m, 2H), 2.04 (brs, NH), 2.20 (m, 1H), 2.55 (t, J=11.6 Hz, 2H), 3.01 (m, 2H), 3.23 (brs, 2H), 3.51 (d, J=10.4 Hz, 1H), 3.52 (brs, 2H), 7.15 (m, 1H), 7.27 (m, 8H); δ_(C-13) (100 MHz, CDCl₃) 12.8, 14.1, 32.2, 39.0, 39.9, 43.1, 46.5, 59.0, 126.1, 126.5, 127.9, 128.0, 128.3, 134.8, 143.0, 144.7, 171.0.

Example 50

[0372] Preparation of N N-Diethyl-4-(3-methoxybenzyl-1-piperazinyl)-benzamide

[0373] Procedure as for N,N-Diethyl-4-[(2,5,5-trimethyl-1-piperazinyl)-3-methoxybenzyl]-benzamide. N,N-Diethyl-4-(chloro-3-methoxybenzyl)-benzamide (1.6 g, 4.8 mmol) was reacted with piperazine (1.6 g, 19 mmol) in acetonitrile (20 mL) for 4 h at 80° C. to give a total of 1.1 g product (63%) which was converted into the dihydrochloride salt. Mp: 165-82° C. IR (amine, CDCl₃ in KBr cell) (cm−1): 3688, 1611, 1458, 1436, 1285. MS(free amine): 381, 336, 296, 224, 196, 165, 152, 112. ¹H NMR: (amine, CDCl₃): δ=1.05, 1.15 (2 br. s, 6H, 2Me), 2.51, 3.02 (2br. s, 8H, piperazine-H), 3.2, 3.45 (2 br. s, 4H, MeCH₂) 3.72, 3.73 (2s, 3H, MeO), 4.21 (s, 1H, CHAr₂), 4.5 (br. s, 1H, NH), 6.60-7.40 (m, 8H, Ar—H). C₂₃H₃₁N₃O₂×2HCl×0.80H₂O requires: C, 58.92; H, 7.44; N, 8.96. Found: C, 58.98; H, 7.76; N, 8.86.

Example 51

[0374] Preparation of N,N-Diethyl-4-[(4-ally-1-piperazinyl)-3-methoxybenzyl]-benzamide

[0375] Procedure as for N,N-Diethyl-4-[(4-allyl-2,5,5-triethyl-1-piperazinyl)-3-methoxybenzyl]-benzamide.

[0376] N,N-Diethyl-4-(3-methoxybenzyl-1-piperazinyl)-benzamide (0.16 g, 0.42 mmol) gave 30 mg product (20%) which was converted to dihydrochloride salt. Mp: 151-76° C. IR (amine, CDCl₃ in KBr cell) (cm−1): 3688, 1611, 1457, 1435, 1288. MS(free amine): 421, 125. ¹H NMR: (amine, CDCl₃): δ=1.1 (2 br. s, 6H, 2Me), 2.3-2.6 (br. s, 8H, piperazine-H), 3.00 (m, 2H, allyl-H), 3.2-3.5 (2 br. s, 4H, MeCH₂), 3.78 (s, 3H, MeO), 4.20 (s, 1H, CHAr₂), 5.14 (m, 2H, allyl-H), 5.85 (m, 1H, alkyl-H), 6.70-7.46 (m, 8H, Ar—H). C₂₆H₃₅N₃O₂×2HCl×1.4H₂O requires: C, 60.09; H, 7.72; N, 8.08. Found C, 60.12; H, 7.59; N, 7.88.

[0377] The compounds of Examples 52-55 were synthesized as shown in Scheme 16 above.

[0378] U.

[0379] Compound I: 4-(α-hydroxybenzyl)-nitrobenzene

[0380] 4-nitrobenzoin (4.55 g, 20.1 mmol) was dissolved in 70 ml of anhydrous methanol cooled down to 0° C. in an ice bath, NaBH (0.915 g, 24.2 mmol) was then added under N₂, the mixture was stirred at r.t., for overnight, quenched with NH₄Cl sat'd aqueous solution, MeOH was evaporated and EtOAc was added, the mixture was washed with water, the organic layer was dried over MgSO₄ and concentrated to give a solid as the desired product (−4.58 g, ˜100% yield).

[0381]¹H NMR (CDCl₃, TMS):δ(ppm): 2.40 (s, br, 1H, OH); 5.92 (d, J=3.2 Hz, 1H, Ar—CH—OH); 7.30-7.40 (m, 5H, Ar); 7.58 (d, J=8.6, 2H, Ar—NO₂); 8.18 (d, J=8.6 Hz, 2H, Ar—Ne).

[0382] Compound II: 4-(α-chlorobenzyl)-nitrobenzene

[0383] Compound I (4.58 g, 20 mmol) was dissolved in anhydrous CH₂Cl₂, thionyl chloride (4.68 g, 39.4 mmol) was then added to the mixture under N₂, the reaction mixture was refluxed for 5 hr and was cooled down to r.t., the solvent and excess of thionyl chloride were evaporated under vacuum to give a yellowish solid as the desired product (−100% yield).

[0384]¹H NMR (CDCl₃, TMS):δ(ppm): 6.16 (s, 1H, —CH—Cl); 7.30-7.40 (m, 5H, Ar); 7.59 (d, J=8.6 Hz, 2H, Ar—NO₂); 8.20 (d, J=8.6 Hz, 2H, Ar—NO₂).

[0385] Compound III: 4-(N-benzyl-1-piperazinyl)benzyl]-nitrobenzene

[0386] To compound II (11.0 g, 4.1 mmol) and N-benzylpiperazine (1.45 g, 8.2 mmol) dissolved in anhydrous acetonitrile, catalytic amount of potassium carbonate was added and the reaction mixture was then refluxed overnight. After cooling down to r.t, the mixture was washed with brine, the organic layer was concentrated under vacuum to give an oil, it was then purified by MPLC using CH₂Cl₂/MeO NH₄OH=95/5/1 as the eluent to give the pure desired product (1.2 g, 76% yield).

[0387]¹H NMR(CDCl₃, TMS):δ: 2.41-2.48 (8H, br, piperazin ring), 3.51 (2H, s, Ph-CH ₂), 4.34 (1H, s, Ar—CH—Ar), 7.20-8.12 (14H, Ar)ppm.

[0388]¹³C NMR(CDCl₃, TMS): δ: 51.7, 53.1, 62.9, 75.5, 123.8, 127.0, 128.1, 128.5, 128.7, 129.2, 137.9, 140.9, 146.8, 150.6 ppm.

Example 52

[0389] Preparation of 4-[(N-benzyl-piperazinyl)-benzyl]-aniline (Compound 91)

[0390] To compound III (900 mg, 2.33 mmol) dissolved in 10 ml of MeOH, Ra—Ni (150 mg) was added and the temperature was increased to 35° C., hydrazine (380 mg, 11.63 mmol) was then added slowly via a syringe while it was stirring, the temperature of the mixture was increased to 70° C., until the evolution of the gas seized, the reaction mixture was cooled down to r.t., filtered over celite and concentrated to give an oil, which was purified by MPLC using CH₂Cl₂/MeOH=99/1-99/5 as the eluent to give a yellowish solid as the desired product (660 mg, ˜80% yield).

[0391] Elemental Analysis Calcd.for: C₂₄H₂N₃.0.2H₂O: C, 79.64; H, 7.43; N, 11.55. Found: C, 79.83; H, 7.65; N, 11.64.

[0392] IR(NaCl Film): v=2807, 1620, 1513, 1451, 1282, 1137 cm⁻¹.

[0393]¹H NMR(CDCl₃, TMS):δ: 2.3-2.48 (8H, br, piperazine ring), 3.45 (2H, s, br, —NH ₂), 3.48 (2H, s, Ph—CH ₂), 4.10 (1H, s, Ar—CH—Ar), 6.51 (2H, m, Ar), 7.11-7.37 (12H, m, Ar)ppm.

Example 53

[0394] Preparation of 4-[(N-benzyl-1-piperazinyl)-benzyl]-acetanilide (Compound 92)

[0395] To 4-[(N-benzyl-1-piperazinyl)benzyl]-aniline (compound 91) (50 mg, 0.14 mmol) and anhydrous pyridine (excess) were dissolved in anhydrous dichloromethane, followed by the addition of acetic anhydride (4 eq.). The reaction mixture was stirred at r.t., for 30 min. and quenched by H₂O, then washed with sat'd NaHCO₃ aqueous solution and brine, the organic layer was dried over anhydrous MgSO₄, filtered and concentrated to give an oil as the product (44 mg, 80% yield).

[0396]¹H NMR: (CDCl₃, TMS) δ: 2.1(3H, s, —CH ₃), 2.3-2.48 (8H, br, pipyrazin ring), 3.48 (2H, s, Ph—CH ₂), 4.16 (1H, s, Ar—CH—Ar), 7.20-8.12 (14H, Ar)ppm.

[0397] Elemental Analysis Calcd.for: C₂₆H₂₉N₃O.2.1HCl.0.3H₂O: C, 64.83; H, 6.64; N, 8.40. Found: C, 64.86; H, 6.64; N, 8.73

Example 54

[0398] Preparation of 4-[(N-benzyl-1-piperazinyl)-benzyl]-methanesulfonamide

[0399] To 4-[(N-benzyl-1-piperazinyl)-benzyl]-aniline (compound 91) (100 mg, 0.28 mmol) and pyridine (excess) were dissolved in anhydrous dichloromethane (5 ml) followed by the addition of methanesufonic anhydride (97.55 mg, 0.56 mmol), the reaction mixture was stirred at rt. for 20 min. followed by TLC, then it was quenched by adding drop of water, 10 ml of EtOAc was added, the mixture was washed with saturated NH₄Cl aqueous solution and brine, the organic layer was dried over MgSO₄, concentrated and purified by MPLC using CH₂Cl₂/MeOH=99/1-95/5 as the solvent to give the pure product as a white solid (˜90 mg, ˜70% yield).

[0400] Melting point: 195-200° C.(dcp.)

[0401]¹H NMR: (CDCl₃, TMS) o: 2.3-2.48 (8H, br, pipyrazin ring), 2.96 (3H, s, CH ₂SO₂), 3.51 (2H, s, Ph—CH ₂), 4.21 (1H, s, Ar—CH—Ar), 6.25 (1H, br, S—NH—), 7.10-7.41 (14H, m, Ar)ppm.

[0402]¹³C NMR:(CDCl₃) δ: 142.4, 140.2, 137.9, 135.3, 129.2, 129.1, 1285, 128.1, 127.9, 127.0, 121.0, 75.5, 63.0, 53.2, 51.8, 39.3 ppm.

[0403] Elemental analysis: Calcd.for: C₂₅H₂₉N₃O₂S. 0.9H₂O: C, 66.46; H, 6.87; N, 9.30. Found: C, 66.53; H, 6.61; N, 9.23.

Example 55

[0404] Preparation of Methyl-N-4-[(N-benzyl-1-piperazinyl)-benzyl]-2-methylacetate

[0405] To 4-[N-benzyl-1-piperazinyl)-benzyl]-aniline (compound 91) (100 mg, 0.28 mmol), Lithium hydride (2.5 mg, 0.3 mmol) and 1-bromomethylacetate (44.16 mg, 0.28 mmol) were mixed in anhydrous THF, the reaction mixture were refluxed for 2 hr. and cooled down to rt., then quenched with drops of water, washed with brine twice, dried over anhydrous MgSO₄ and concentrated to an oil, purified by MPLC using CH₂Cl₂/MeOH=98/2 as the solvent to give an oil as the product (−23 mg, 20% c).

[0406] IR (NaCl Film): HCl salt

[0407] v=3404(br), 2922(br), 1745, 1610, 1517, 1439, 1207 cm⁻¹

[0408]¹H NMR: (CDCl₃) δ: 2.40 (8H, br, piperazine ring), 3.50 (2H, s, Ph—CH ₂), 3.75 (3H, s, —O—CH ₃), 3.85 (2H, d, J=5.2 Hz, N—CH ₂), 4.12 (1H, s, Ar—CH—Ar), 4.18 (1H, t, J=5.2 Hz, Ar—N—CH₂), 6.49 (2H, d, J=9.4 Hz, —N—Ar), 7.14-7.38 (12H, m, Ar)ppm.

[0409] Anal.Calcd.for: C₂₇H₃₁N₃O₂.3HCl: C, 60.17; H, 6.36; N, 7.80. Found: C, 59.97; H, 6.61; N, 7.46.

[0410] Compound IV: 4-(3-fluoro-(α-hydroxybenzyl)-acetonitrile

[0411] To 1-Fluoro-3-iodo-benzene (7.53 g, 33.9 mmol) was dissolved in anhydrous THF and was cooled down to −78° C., n-Butyllithium (2.5M in THF, 33.9 mmol) was added slowly into the reaction mixture via a syringe, the mixture was stirred for 10 min. followed by the addition of the solution of 4-Acetamidobenzaldehyde (1.84 g, 11.3 mmol) in 5 ml of dry DME, the reaction mixture was then stirred at −78° C. for 30 min. before quenched with NH₄Cl aqueous solution. The organic layer was washed with brine and dried over anhydrous MgSO₄, filtered and concentrated to an oil, purified by MPLC using 10% heptane in CH₂O₂ and 100% CH₂Cl₂ to give the pure product (1.65 g, 56% yield).

[0412]¹H NMR: (CDCl₃) δ: 2.14 (3H, s, OCCH ₃), 2.55 (1H, s, br. OH), 5.76 (1H, d, J=3.2 Hz, Ar—CH—Ar), 7.35 (1H, s, CONH), 6.90-7.50 (8H, m, Ar)ppm.

[0413] Compound V: 4-(3-fluoro-α-chlorobenzyl)-acetonitrile

[0414] This was prepared using the same method as described for the preparation of compound (II) but using compound (IV). It was used directly for the next step reaction without purification.

[0415]¹H NMR: (CDCl₃) δ: 2.15 (3H, s, OCCH ₃), 6.10 (1H, s, Ar—CH—Ar), 7.84 (1H, s, CONH), 6.9˜7.6 (8H, m, Ar), 7.84 (1H, s, CONH)ppm

Example 56

[0416] Preparation of 4-[(N-benzyl-1-piperazinyl)-3-fluorobenzyl]-acetanilide (Compound 95)

[0417] This was prepared using the same method as described for the preparation of compound (III) but using compound (V).

[0418]¹H NMR: (CDCl₃) δ: 2.14 (3H, s, OCCH ₃), 2.40 (8H, br, piperazine), 3.51 (2H, s, Ph—CH ₂), 4.19 (1H, s, Ar—CH—Ar), 6.80-7.40 (13H, m, Ar)ppm.

[0419] Analysis:

[0420] Anal.Calcd.for: C₂₆H₂₈FN₃O.2HCl.1.6CH₂Cl₂.2H₂O: C, 56.24; H, 6.02; N, 7.13. Found: C, 56.29; H, 6.10; N, 6.88.

[0421] Pharmaceutical Compositions

[0422] The novel compounds according to the present invention may be administered per orally, intramuscularly, subcutaneously, intraperitoneally, intrathoracially, intravenously, intrathecally and intracerebroventricularly.

[0423] The dosage will depend on the route of administration, the severity of the disease, age and weight of the patient and other factors normally considered by the attending physician, when determining the individual regimen and dosage level at the most appropriate for a particular patient.

[0424] For preparing pharmaceutical compositions from the compounds of this invention, inert, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, dispersible granules, capsules, cachets, and suppositories.

[0425] A solid carrier can be one or more substances which may also act as diluents, flavoring agents, solubilizers, lubricants, suspending agents, binders, or tablet disintegrating agents; it can also be an encapsulating material.

[0426] In powders, the carrier is a finely divided solid which is in a mixture with the finely divided active component. In tablets, the active component is mixed with the carrier having the necessary binding properties in suitable proportions and compacted in the shape and size desired.

[0427] For preparing suppository compositions, a low-melting wax such as a mixture of fatty acid glycerides and cocoa butter is first melted and the active ingredient is dispersed therein by, for example, stirring. The molten homogeneous mixture is then poured into convenient sized molds and allowed to cool and solidify.

[0428] Suitable carriers are magnesium carbonate, magnesium stearate, talc, lactose, sugar, pectin, dextrin, starch, tragacanth, methyl cellulose, sodium carboxymethyl cellulose, a low-melting wax, cocoa butter, and the like.

[0429] Pharmaceutically acceptable salts are acetate, benzenesulfonate, benzoate, bicarbonate, bitartrate, bromide, calcium acetate, camsylate, carbonate, chloride, cetrate, dihydrochloride, edetate, edisylate, estolate, esylate, fumarate, glucaptate, gluconate, glutamate, glycollylarsanilate, hexytresorcinate, hydrabamine, hydrobromide, hydrochloride, hydroxynaphthoate, iodide, isethionate, lactate, lactobionate, malate, maleate, mandelate mesylate, methylbromide, methylnitrate, methylsulfate, mucate, napsylate, nitrate, pamoate (embonate), pantothenate, phosphate/diphosphate, polygalacturonate, salicylate, stearate, subacetate, succinate, sulfate, tannata, tartrate, teoclate, triethiodide, benzathine, chloroprocaine, choline, diethanolamine, ethylenediamine, meglumine, procaine, aluminium, calcium, lithium, magnesium, potassium, sodium, and zinc.

[0430] Preferred pharmaceutically acceptable salts are the hydrochlorides and citrates.

[0431] The term composition is intended to include the formulation of the active component with encapsulating material as a carrier providing a capsule in which the active component (with or without other carriers) is surrounded by a carrier which is thus in association with it. Similarly, cachets are included.

[0432] Tablets, powders, cachets, and capsules can be used as solid dosage forms suitable for oral administration.

[0433] Liquid from compositions include solutions, suspensions, and emulsions. Sterile water or water-propylene glycol solutions of the active compounds may be mentioned as an example of liquid preparations suitable for parenteral administration. Liquid compositions can also be formulated in solution in aqueous polyethylene glycol solution.

[0434] Aqueous solutions for oral administration can be prepared by dissolving the active component in water and adding suitable colorants, flavoring agents, stabilizers, and thickening agents as desired. Aqueous suspensions for oral use can be made by dispersing the finely divided active component in water together with a viscous material such as natural synthetic gums, resins, methyl cellulose, sodium carboxymethyl cellulose, and other suspending agents known to the pharmaceutical formulation art.

[0435] Preferably the pharmaceutical compositions is in unit dosage form. In such form, the composition is divided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of the preparations, for example, packaged tablets, capsules, and powders in vials or ampoules. The unit dosage form can also be a capsule, cachet, or tablet itself, or it can be the appropriate number of any of these packaged forms.

[0436] Biological Evaluation

[0437] A) In Vitro Model

[0438] Cell Culture

[0439] Human 293S cells expressing cloned human μ, δ, and κ receptors and neomycin resistance were grown in suspension at 37° C. and 5% CO₂ in shaker flasks containing calcium-free DMEM 10% FBS, 5% BCS, 0.1% Pluronic F-68, and 600 μg/ml geneticin.

[0440] Membrane Preparation

[0441] Cells were pelleted and resuspended in lysis buffer (50 mM Tris, pH 7.0, 2.5 mM EDTA, with PMSF added just prior to use to 0.1 mM from a 0.1 M stock in ethanol), incubated on ice for 15 min, then homogenized with a polytron for 30 sec. The suspension was spun at 1000 g (max) for 10 min at 4° C. The supernatant was saved on ice and the pellets resuspended and spun as before. The supernatants from both spins were combined and spun at 46,000 g (max) for 30 min. The pellets were resuspended in cold Tris buffer (50 mM Tris/Cl, pH 7.0) and spun again. The final pellets were resuspended in membrane buffer (50 mM Tris, 0.32 M sucrose, pH 7.0). Aliquots (1 ml) in polypropylene tubes were frozen in dry ice/ethanol and stored at −70° C. until use. The protein concentrations were determined by a modified Lowry assay with SDS.

[0442] Binding Assays

[0443] Membranes were thawed at 37° C., cooled on ice, passed 3 times through a 25-gauge needle, and diluted into binding buffer (50 mM Tris, 3 mM MgCl₂, 1 mg/ml BSA (Sigma A-7888), pH 7.4, which was stored at 4° C. after filtration through a 0.22 m filter, and to which had been freshly added 5 μg/ml aprotinin, 10 μM bestatin, 10 μM diprotin A, no DTT). Aliquots of 100 μl (for μg protein, see Table 1) were added to iced 12×75 mm polypropylene tubes containing 100 μl of the appropriate radioligand (see Table 1) and 100 μl of test peptides at various concentrations. Total (TB) and nonspecific (NS) binding were determined in the absence and presence of 10 μM naloxone respectively. The tubes were vortexed and incubated at 25° C. for 60-75 min, after which time the contents are rapidly vacuum-filtered and washed with about 12 ml/tube iced wash buffer (50 mM Tris, pH 7.0, 3 mM MgCl₂) through GF/B filters (Whatman) presoaked for at least 2 h in 0.1% polyethyleneimine. The radioactivity (dpm) retained on the filters was measured with a beta counter after soaking the filters for at least 12 h in minivials containing 6-7 ml scintillation fluid. If the assay is set up in 96-place deep well plates, the filtration is over 96-place PEI-soaked unifilters, which were washed with 3×1 ml wash buffer, and dried in an oven at 55° C. for 2 h. Th e filter plates were counted in a TopCount Packard) after adding 50 μl MS-20 scintillation fluid/well.

[0444] Data Analysis

[0445] The specific binding (SB) was calculated as TB-NS, and the SB in the presence of various test peptides was expressed as percentage of control SB. Values of IC₅₀ and Hill coefficient (n_(H)) for ligands in displacing specifically bound radioligand were calculated from logit plots or curve fitting programs such as Ligand, GraphPad Prism, SigmaPlot, or ReceptorFit. Values of K_(i) were calculated from the Cheng-Prussoff equation. Mean±S.E.M. values of IC₅₀, K_(i) and n_(H) were reported for ligands tested in at least three displacement curves.

[0446] Receptor Saturation Experiments

[0447] Radioligand K_(δ) values were determined by performing the binding assays on cell membranes with the appropriate radioligands at concentrations ranging from 0.2 to 5 times the estimated K_(δ) (up to 10 times if amounts of radioligand required are feasable). The specific radioligand binding was expressed as pmole/mg n protein. Values of K and B_(max) from individual experiments were obtained from nonlinear fits of specifically bound (B) vs. nM free (F) radioligand from individual according to a one-site model.

[0448] B) Biological Model (In Vivo Model)

[0449] Freund's Complete Adjuvant (FCA), and Sciatic Nerve Cuff Induced Mechano-Allodynia in Rat

[0450] Animals

[0451] Male Sprague-Dawley rats (Charles River, St-Constant, Canada) weighing 175-200 g at the time of surgery were used. They were housed in groups of three in rooms thermostatically maintained at 20° C. with a 12:12 hr light/dark cycle, and with free access to food and water. After arrival, the animals were allowed to acclimatize for at least 2 days before surgery. The experiments were approved by the appropriate Medical Ethical Committee for animal studies.

[0452] Experimental Procedure

[0453] Freund's Complete Adjuvant

[0454] The rats were first anesthetized in a Halothane chamber after which 10 μl of FCA was injected s.c. into the dorsal region of the left foot, between the second and third external digits. The animals were then allowed to recover from anesthesia under observation in their home cage.

[0455] Sciatic Nerve CF

[0456] The animals were prepared according to the method described by Mosconi and Kruger (1996). Rats were anesthetized with a mixture of Ketamine/Xylazine i.p. (2 ml/g) and placed on their right side and an incision made over, and along the axis of, the lateral aspect of the left femur. The muscles of the upper quadriceps were teased apart to reveal the sciatic nerve on which a plastic cuff (PE-60 tubing, 2 mm long) was placed around. Mme wound was then closed in two layers with 3-0 vicryl and silk suture

[0457] Determination of Mechano-Allodynia Using Von Frey Testing

[0458] Testing was performed between 08:00 and 16:00 h using the method described by Chaplan et al. (1994). Rats were placed in Plexiglas cages on top of a wire mesh bottom which allowed access to the paw, and were left to habituate for 10-15 min. The area tested was the mid-plantar left hind paw, avoiding the less sensitive foot pads. The paw was touched with a series of 8 Von Frey hairs with logarithmically incremental stiffness (0.41, 0.69, 1.20, 2.04, 3.63, 5.50, 8.51, and 15.14 grams; Stoelting, Ill., USA). The von Frey hair was applied from underneath the mesh floor perpendicular to the plantar surface with sufficient force to cause a slight buckling against the paw, and held for approximately 6-8 seconds. A positive response was noted if the paw was sharply withdrawn. Flinching immediately upon removal of the hair was also considered a positive response. Ambulation was considered an ambiguous response, and in such cases the stimulus was repeated.

[0459] Testing Protocol

[0460] The animals were tested on postoperative day 1 for the FCA-treated group and on post-operative day 7 for the Sciatic Nerve Cuff group. The 50% withdrawal threshold was determined using the up-down method of Dixon (1980). Testing was started with the 2.04 g hair, in the middle of the series. Stimuli were always presented in a consecutive way, whether ascending or descending. In the absence of a paw withdrawal response to the initially selected hair, a stronger stimulus was presented; in the event of paw withdrawal, the next weaker stimulus was chosen. Optimal threshold calculation by this method requires 6 responses in the immediate vicinity of the 50% threshold, and counting of these 6 responses began when the first change in response occurred, e.g. the threshold was first crossed. In cases where thresholds fell outside the range of stimuli, values of 15.14 (normal sensitivity) or 0.41 (maximally allodynic) were respectively assigned. The resulting pattern of positive and negative responses was tabulated using the convention, X=no withdrawal; O=withdrawal, and the 50% withdrawal threshold was interpolated using the formula:

50% g threshold=10^((Xf+*kδ))/10,000

[0461] where Xf=value of the last von Frey hair used (log units); k=tabular value (from Chaplan et al. (1994)) for the pattern of positive/negative responses; and δ=mean difference between stimuli (log units). Here δ=0.224.

[0462] Von Frey thresholds were converted to percent of maximum possible effect (% MPE), according to Chaplan et al. 1994. The following equation was used to compute % MPE:

% MPE=Drug treated threshold (g)−allodynia threshold (g)×100 Control threshold (g)−allodynia threshold (g)

[0463] Administration of Test Substance

[0464] Rats were injected (subcutaneously, intraperitoneally, or orally) with a test substance prior to von Frey testing, the time between administration of test compound and the von Frey test varied depending upon the nature of the test compound. 

1. A compound of the general formula (I)

wherein G is a carbon atom or a nitrogen atom; A is selected from (i) phenyl substituted by any of —COOH, —CONH₂, COOCH₃, —CN, NH₂ or —COCH₃; (ii) naphtyl, benzofuranyl, and quinolinyl; and

 wherein the phenyl ring of each A substituent may be optionally and independently substituted by 1 or 2 substituents selected from hydrogen, CH₃, (CH₂)_(o)CF₃, halogen, CONR⁷R⁸, CO₂R⁷, COR⁷, (CH₂)_(o)NR⁷R⁸, (CH₂)_(o)CH₃(CH₂)_(o)SOR⁷, (CH₂)_(o)SO₂R⁷ and (CH₂)_(o)SO₂NR⁷R⁸ wherein o is 0, 1, or 2, and R⁷ and R⁸ are as defined below; R¹ is selected from hydrogen; a branched or straight C₁-C₆ alkyl, C₁-C₆ alkenyl, —CO(C₁-C₆ alkyl); (C₁-C₆ alkyl)-B wherein B is as defined below; C₃-C₈ cycloalkyl, C₄-C₈ (alkyl-cycloalkyl) wherein alkyl is C₁-C₂ alkyl and cycloalkyl is C₃-C₆ cycloalkyl; C₆-C₁₀ aryl; and heteroaryl having from 5-10 atoms selected from any of C, S, N and O; and whereby the C₆-C₁₀ aryl and the heteroaryl may optionally be substituted by 1 or 2 substituents selected from hydrogen, CH₃, (CH₂)_(o)CF₃, halogen, CONR⁷R⁸, CO₂R⁷, COR⁷, (CH₂)_(o)NR⁷R⁸, (CH₂)_(o)CH₃(CH₂)_(o)SOR⁷, (CH₂)_(o)SO₂R⁷ and (CH₂)_(o)SO₂NR⁷R⁸ wherein o is 0, 1, or 2, and R⁷ and R⁸ are as defined below; R⁷ and R⁸ is each and independently as defined for R¹ above; R² is selected from hydrogen, CH₃, OR¹, CO₂R¹, and CH₂CO₂R¹ wherein R¹ is as defined above; R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, and R¹⁸, is each and independently as defined for R1 above; B is a substituted or unsubstituted aromatic; an optionally substituted C₅-C₁₀ hydroaromatic; a heteroaromatic or a heterohydroaromatic moiety, each having from 5 to 10 atoms selected from any of C, S, N and O, and each being optionally substituted by 1 or 2 substituents independently selected from hydrogen, CH₃, CF₃, halogen, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)COR⁷, (CH₂)_(p)CO₂R⁷, (CH₂)_(p)SOR⁷, (CH₂)_(p)SO₂R⁷, and (CH₂)_(p)SO₂NR⁷R⁸; wherein p is 0, 1, 2 or 3 and wherein R⁷ and R⁸ are as defined above; R³, R⁴, R⁵ and R⁶ is each and independently selected from R⁷, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)CO₂R⁷, (CH₂)_(p)Ph, (CH₂)_(p)(p-OH Ph), (CH₂)_(p)-3-indolyl, (CH₂)_(p)SR⁷, and (CH₂)_(p)OR⁷; wherein p is 0, 1, 2, 3, or 4, and R⁷ and R⁸ are as defined above; as well as pharmaceutically acceptable salts of the compounds of the formula (I), isomers, hydrates, isoforms and prodrugs thereof; with the proviso that when A is a phenyl ring substituted by a —CN group or by a —NH₂ group, B may not be

 wherein Z¹ is hydroxy, and esters thereof; hydroxymethyl, and esters thereof; or amino, and carboxamides and sulfonamides.
 2. A compound of the formula I according to claim 1, wherein G is a carbon atom or a nitrogen atom; A is selected from (i) phenyl substituted by any of —COOH, —CONH₂, COOCH₃, —CN, NH₂ or —COCH₃; (ii) naphtyl, benzofuranyl, and quinolinyl; and (iii)

 wherein the phenyl ring of each A substituent may be optionally and independently substituted by 1 or 2 substituents selected from hydrogen, CH₃, (CH₂)_(o)CF₃, halogen CONR⁷R⁸, CO₂R⁷, COR⁷, (CH₂)_(o)NR⁷R⁸, (CH₂)_(o)CH₃(CH₂)_(o)SOR⁷, (CH₂)_(o)SO₂R⁷ and (CH₂)_(o)SO₂NR⁷R⁸ wherein o is 0, 1, or 2, and R⁷ and R⁸ are as defined below; R¹, R⁷ and R⁸ is each and independently selected from hydrogen; a branched or straight C₁-C₄ alkyl, allyl, —CO—(C₁-C₆ alkyl); (C₁-C₆ alkyl)-B wherein B is as defined below, C₃-C₅ cycloalkyl, C₄-C₈ (alkyl-cycloalkyl) wherein alkyl is C₁-C₂ alkyl and cycloalkyl is C₃-C₆ cycloalkyl; and phenyl; R² is hydrogen, methyl, or OR¹ wherein R¹ is as defined above; R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, and R¹⁸ is each and independently as defined for R¹ above; B is selected from phenyl, naphthyl, indolyl, benzofuranyl, dihydrobenzofuranyl, benzothiophenyl, pyrryl, furanyl, quinolinyl, isoquinolinyl, cyclohexyl, cyclohexenyl, cyclopentyl, cyclopentenyl, indanyl, indenyl, tetrahydronaphthyl, tetrahydroquinyl, tetrahydroisoquinolinyl, tetrahydrofuranyl, pyrrolidinyl, indazolinyl, and

 each B group being optionally substituted by 1-2 substituents independently selected from hydrogen, CH₃, CF₃, halogen, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)COR⁷, (CH₂)_(p)(CO₂R⁷, and OR⁷, wherein p is 0 or 1, and wherein R⁷ and R⁸ are as defined above; and R³, R⁴, R⁵ and R⁶ is each and independently selected from hydrogen, CH₃, CH(Me)₂, CH₂CH(Me)₂, CH(Me)CH₂CH₃(CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)CO₂R⁷, (CH₂)_(p)Ph, (CH₂)_(p)(p-OH Ph), (CH₂)_(p)-3-indolyl, (CH₂)_(p)SR⁷, and (CH₂)_(p)OR⁷, wherein p is 0, 1, 2, or 3, and wherein R⁷ and R⁸ are as defined above; with the proviso that when A is a phenyl ring substituted by a —CN group or by a —NH₂ group, B may not be

 wherein Z¹ is hydroxy, and esters thereof; hydroxymethyl, and esters thereof; or amino, and carboxamides and sulfonamides.
 3. A compound of the formula I according to claim 1, wherein G is a nitrogen atom; A is selected from

 wherein R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, and R¹⁸ is each an ethyl group; R¹ is selected from hydrogen, methyl, ethyl, allyl, or CH₂-cyclopropyl; R² is H, methyl, or OR¹; B is selected from phenyl, naphthyl, indolyl, benzofuranyl, dihydrobenzofuranyl, benzothiophenyl, furanyl, quinolinyl, isoquinolinyl, cyclohexyl, cyclohexenyl, cyclopentyl, cyclopentenyl, indanyl, indenyl, tetrahydronaphthyl, tetrahydroquinyl, tetrahydroisoquinolinyl, tetrahydrofuranyl, indazolinyl, and

 each B group being optionally substituted by 1-2 substituents-independently selected from hydrogen, methyl, CF₃, halogen, (CH₂)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)COR⁷, (CH₂)_(p)C₂R⁷, and OR⁷, wherein p is 0, 1, or 2, and wherein R⁷ and R⁸ are as defined for R¹ above; R³, R⁴, R⁵ and R⁶ is each and independently selected from H, CH₃, CH(Me)₂, CH₂CH(Me)₂, CH(Me)CH₂CH₃(CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)NR⁷R⁸, (CH₂)_(p)CONR⁷R⁸, (CH₂)_(p)CO₂R⁷, (CH₂)_(p)Ph, (CH₂)_(p)(p-OH Ph), (CH₂)_(p)SR⁷, and (CH₂)_(p)OR⁷ wherein p is 0, 1 or 2, and wherein R⁷ and R⁸ are as defined above.
 4. A compound of the formula (I) of claim 1 above, being anyone of (±)-trans-1-(3-methoxy-α-(naphthyl)benzyl)-2,5-dimethylpiperazine (compound 3); (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-1-naphthyl)anisole (compound 4 and 5); (±)-trans-1-(3-methoxy-α-(2-naphthyl)benzyl)-2,5-dimethylpiperazine (compound 8); (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-2-naphthyl)anisole (compound 9 and 10); (±)-trans-1-(3-methoxy-α-(2′-benzofuranyl)benzyl)-2,5-dimethylpiperazine (compound 13); (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-2-benzofuranyl)anisole (compound 14 and 15); (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Cyclopropylmethyl-2,5-dimethyl-1-piperazinyl)-2-benzofuranyl)anisole (compound 16 and 17); (±)-trans-1-(3-methoxy-α-(6′-quinolinyl)benzyl)-2,5-dimethylpiperazine (compound 20 and 21); (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-6-quinolinyl)anisole (compound 22); (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Allyl-2,5-dimethyl-1-piperazinyl)-6-quinolinyl)anisole (compound 23); (±)-3-((αR*/S*)-α-((2S*,5R*)-4-Cyclopropylmethyl-2,5-dimethyl-1-piperazinyl)-6-quinolinyl)anisole (compound 24 and 25); (±)-trans-1-(3-methoxy-α-(4-quinolinyl)benzyl)-2,5-dimethyl-piperazine (compound 28); (±)-3-((αR*/S*)-α-((2S*,5R*) Allyl-2, ethyl-1-piperazinyl)-4-quinolinyl)anisole (compound 29 and 30); (±)4-((α-(1-Piperazinyl))-4-chlorobenzyl)-N,N-diethylbenzamide (compound 33); (±)4-((α-((4-Allyl)-1-piperazinyl))-4-chlorobenzyl)-N,N-diethylbenzamide.2hcl (compound 34); (±)4-((α-(1-Piperazinyl))-2-naphtylmethyl)-N,N-diethylbenzamide (compound 37); (±)4-((α-((4-Allyl)-1-piperazinyl)-2-naphtylmethyl)-N,N-diethylbenzamide (compound 38); (±)4-((α-(1-Piperazinyl))-4-xylyl)-N,N-diethylbenzamide, (compound 41); (±)4-((α-((4-Allyl)-1-piperazinyl))-4-xylyl)-N,N-diethylbenzamide.2HCl (compound 42); (±)4-((α-(1-Piperazinyl))-3-xylyl)-N,N-diethylbenzamide.2HCl (compound 45); (±)4-((α-(1-Piperazinyl))-cyclohexylmethyl)-N,N-diethylbenzamide (compound 48); (±)4-((α-(1-Piperazinyl))-3,4-dimethylbenzyl)-N,N-diethylbenzamide (compound 51); (±)4-((α-(1-Piperazinyl))-1-naphtylmethyl)-N,N-diethylbenzamide (compound 54); 4-(4-(2-Dimethyl-5-methyl-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide dihydrochloride (compound 57); 4-(4-(1-Allyl-2-dimethyl-5-methyl-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide dihydrochloride (compound 58); 4-(1-(4-Allyl-2-dimethyl-5-methyl-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide dihydrochloride (compound 60); 4-(1-(2-dimethyl-5-methyl-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide dihydrochloride (compound 61); 4-((1-piperazinyl)-benzyl) N,N-diethylbenzamide dihydrochloride (compound 64); 4-((4-Allyl-1-piperazinyl)-benzyl)-N,N-diethylbenzamide dihydrochloride (compound 65); 4-((4-Acetyl-1-piperazinyl)-benzyl)-N,N-diethylbenzamide hydrochloride (compound 77); 4-(4-(2-Hydroxymethyl-5-methyl)piperazinyl-benzyl)-N,N-diethyl-benzamide dihydrochloride (compound 69); 4-((4-(2-Hydroxymethyl-5-methyl)piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide dihydrochloride (compound 70); 4-((4-(1-Allyl-2-hydroxymethyl-5-methyl)piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide dihydrochloride (compound 71); Methyl 3-((2-naphtyl)(3-methyl-piperazinyl)methyl)phenyl ether dihydrochloride (compound 75); Methyl 3-((2-naphtyl)(4-Allyl-2-methyl-piperazinyl)methyl)phenyl ether dihydrochloride (compound 76); 4-((1-piperazinyl)benzyl)benzoic acid dihydrochloride (compound 79); 4-((1-piperazinyl)benzyl-N,N-diethylbenzamide hydrochloride (compound 83); Methyl 4-((4-t-butoxycarbonyl-piperazinyl)-benzyl)benzoate (compound 80); Methyl 4-((1-piperazinyl)benzyl)benzoate dihydrochloride (compound 81); 4-(1-piperazinyl-benzyl)benzonitrile dihydrochloride (compound 84); 4-(1-piperazinyl-benzyl)-acetophenone dihydrochloride (compound 85); 4-((α-piperidinyl)-benzyl)-N,N-diethylbenzmide (compound 88); N,N-Diethyl-4-(3-methoxybenzyl-1-piperazinyl)-benzamide (Example 50); N,N-Diethyl-4-[(4-allyl-1-piperazinyl)-3-methoxybenzyl]-benzamide (Example 51); 4-[(N-benzyl-1-piperazinyl)-benzyl]-aniline (compound 91); 4-[(N-benzyl-1-piperazinyl)-benzyl]-acetanilide (compound 92); 4-[(N-benzyl-1-piperazinyl)-benzyl]-methanesulfonamide (Example 54); Methyl-N-4-[(N-benzyl-1-piperazinyl)-benzyl]-2-methylacetate Example 55); and 4-[(N-benzyl-1-piperazinyl)-3-fluorobenzyl]-acetanilide (compound 95).
 5. A compound according to any of claims 1-4, in form of its hydrochloride salt.
 6. A compound according to any of claims 1-5, for use in therapy.
 7. A compound according to claim 6, wherein the therapy is pain management.
 8. A compound according to claim 6, wherein the therapy is directed towards gastrointestinal disorders.
 9. A compound according to claim 6, wherein the therapy is directed towards spinal injuries.
 10. A compound according to claim 6, wherein the therapy is directed to disorders of the sympathetic nervous system.
 11. Use of a compound according to any of claims 1-5 for the manufacture of a medicament for use in the treatment of pain.
 12. Use of a compound according to any of claims 1-5 for the manufacture of a medicament for use in the treatment of gastrointestinal disorders.
 13. Use of a compound according to any of claims 1-5 for the manufacture of a medicament for use in the treatment of spinal injuries.
 14. A compound according to any of claims 1-5, further characterized in that it is isotopically labelled.
 15. Use of a compound according to claim 14 as a diagnostic agent.
 16. A pharmaceutical composition comprising a compound according to any of claims 1-5 as an active ingredient, together with a pharmaceutically acceptable carrier.
 17. A process for the preparation of a compound according to any of claims 1-5, whereby A) (i) An aldehyde or ketone is treated with a nucleophile, giving the corresponding alcohol;  (ii) the alcohol is converted into a suitable leaving group, which in turn is displaced with a nucleophile; and  (iii) a N-(4)-unsubstituted piperazine derivative is substituted via its organo halide or equivalent species, or acylated; or B) (i) A N-protected amino acid ester is reacted with a second amino acid ester, and thereafter treated with an acid, giving a piparazinedione;  (ii) the dione is reduced to the corresponding pip raze; and  (iii) the piperazine is alkylated or acylated on one or more of the nitrogens.
 18. A method for the treatment of pain, whereby an effective amount of a compound according to any of claims 1-5 is administered to a subject in need of pain management. 